Phantom Techs vs nepal cubes warmth

I've always used and loved Nepal Cubes, but grabbed a pair of previous-generation Phantom Techs for cheap, hoping that they would allow me to push into slightly colder objectives while also saving ~300g per foot (boot weight diff + elimination of separate gaiters). Now I'm trying to decide which boots to resell. It seems to be common knowledge that a supergaiter "single-and-a-half" boot should be warmer than a single boot.

So far though, my feet have gotten colder in the Phantom Techs than in the Nepals. I believe the weather was actually colder when I tried the Nepals this year than the Phantom Techs, but there were also other confounding factors that differed between the Nepal days and Tech days (activity level, lacing tightness, insoles, toe warmers, caloric intake etc.)

It's really hard to get a fair comparison amid all the confounding factors. So can anyone help me with some additional anecdotal evidence to supplement my own observations? 

The supergaiter is too loose to form a tight seal around my calf. And it's not adjustable. Does the Phantom Techs' supposed warmth depend on the gaiter keeping cold air out?

Ellen Swrote:there were also other confounding factors that differed between the Nepal days and Tech days (activity level, lacing tightness, insoles, toe warmers, caloric intake etc.)

That certainly has a lot to do with it in my opinion. Do you keep your laces loose when not climbing, and tighten for the pitch? That strategy has worked well for me. That allows for better circulation = warmer feet. Overall, I try to avoid taking up too much volume in the boot as well, so I avoid toe warmers for this reason. More volume is also good for circulation. Of course, getting a good fit is important here too, so it's a balance.

The soles on the PT's are thinner than the Cubes, so less insulation under the foot and closer to the cold ground is the trade off here for more sensitivity and weight savings.You could experiment with some more insulated insoles in the PT's, even a thin layer of foil maybe useful. Additionally, the techs overall weigh less. So, I believe there's less insulation in the boot overall.

As far as the supergaiter boots vs single leather boots go, generally speaking I think the supergaiters are prone for trapping moisture inside the boot and being less breathable. None of them are as breathable in the field as they may claim to be in theory. Have you noticed how sweaty your feet/sock gets in either boot? Wet/sweaty feet is a recipe for cold feet. Of course, on the flip side, they'll let less moisture inside the boot in the first place, so if you're climbing in wet conditions/climates, they can be awesome for this reason. I've had leather boots get totally soaked and have had a really bad time because of this. This is kind of the same dilemma when choosing between hardshell and softshell clothing.

At the end of the day, I view them as being different boots, neither one necessarily being better or warmer than the other. You just have to experiment and pay attention to all these different factors and formulate your own opinions and theories from there.

P.S. I'd recommend a double boot in your quiver for the coldest of days. 

I'm happy to chime in with my own anecdotal observations and thoughts. One major caveat though, I've only used the Nepal Cubes (and don't own them anymore...not because of warmth issues, but rather the fit was not great for me) and have not worn the Phantom Techs. I currently have Mammut Magic Guide High's as my "light" boot; Scarpa Mont Blanc's as my "regular" boot; and then TNF Verto S6K as my "really cold" boot (although these rarely come out of my gear bin); so, none of which really replicate the "boot-and-a-half"/supergaiter design of your PTs. I concur with Christian's points on lace tightness, circulation, etc. as having a big influence on feet warmth though, regardless of which boot I'm wearing - maybe vary your sock/insole/lacing mix a few ways with the PTs and see what difference it makes. Moisture management is also a challenge for me - as much as GTX is supposed to be "waterproof and breathable", the leather on the Mammut and heavier leather on the MBs seem to just not move vapor out as well as I'd like. On long approaches, I have to pay pretty close attention to venting my upper body, so I don't sweat and get stuck with wet feet all day. The MBs feel pretty similar to the Cubes in terms of weight and thickness, but I sized up in the MBs and went with a thicker aftermarket insulated insole, and they feel a bit warmer. I do not wear a gaiter with either the Mammut's or MBs, but my climbing pants have a cuff string that I close down over the top of the boot, and I think it does retain a fair bit of warmth. For comparison, I ski tour in Proclines and will often unzip that gaiter on the uptrack for venting, and I definitely notice a difference, so it's certainly possible that the loose supergaiter fit on your PTs is causing you to lose some heat out the top.

I have owned both, climbed the same routes in both and spent many Colorado winter days in both.

I am willing to say Nepal Cubes are warmer. However, more importantly I would encourage you to go with the boot that fits your foot better for long walks and all day comfort. I never felt like the Phantom Tech fit my foot well and am very happy with my LaSportiva's at this time. 

I've used the G5s and more recently the Phantom Techs and the the G5s are definitely warmer.  

I spoke to someone at Scarpa about the insulation and its worth noting that the stock insole has an insulation component, so if you replace that insole with superset, then you might be making it a colder boot.   

Dr Logic wrote:

I have not used the Nepal cubes, just scarpa (3 different boots) and a couple other brands. Phantom techs are not warm. Period. 

I wear them loose until I'm ready to climb. Then I crank them down until l lose circulation, but they climb so much better. I have replaced the laces with Solomon speed laces (two sets, one for foot and one for ankle) so this is easy and quick. I use toe warmers and finally just invested in heated socks (have not yet used).

Just the way it is. It's the only thing that regularly gets cold for me. 

How did the speed laces work out?  I considered something similar, but those versions seemed to have  too much elasticity in the cord that I figured would not work well in securing a foot inside of a climbing boot.  I've been trying some lace locks off amazon that are definitely an improvement over stock, but not as easy as a something like the salmon speed lock. 

https://www.amazon.com/dp/B0037H8CRQ?psc=1&ref=ppx_yo2ov_dt_b_product_details

Dr Logic wrote:

They're mostly great. I'm on my second season with them and I'll need to replace one. Every once in awhile the locking mechanism will get compressed by the gaiter and loosen, but it's easily noticable and quickly fixable. I use two on each boot, one stops right at the ankle start and the other for just around the ankle, which when cranked down stops almost all heel lift. It's a good improvement and considering the speed laces cost $7 per boot, a cheap upgrade. 

However, it also basically cuts off all circulation to my foot making it cold and eventually cramp up, but I think that's more a problem with the boot than with the laces. But since it's quick to loosen and tighten, I just hike with them loose and tighten for the climb. I'm looking forward to the day they finally put an external boa on it, if that ever happens. 

For space reasons, I didn't use the plastic connector for the lace ends, I just tied and burnt the ends together. I used a paper clip that I fashioned into a curved/hooked needle to drag the laces through the lower loops because otherwise putting them on is a nightmare.

 Great, I'm going to give them a go.  I have the newer model of boot, but it should work all the same.   The lace locks have worked well, but you always lose a bit of tension right before you secure.