Sweet thanks, yes price dropped for me too!! Although, They only have medium... Do you know how RAB tops run? I can wear a Medium or Small depending on brand(In Arc'teryx I wear small) I'm 5'11" @160lbs and have long skinny arms. For more of a climbing top I really don't want it to run baggy like my beach and summer hiking tops. I haven't had the pleasure of owning anything RAB but hear good things.
I'm 5'11" 165 (was 175-180 usually) and wear a L in MH, Rab, Pata, etc. I can wear a M in many brands, but usually like the extra length/volume and ability to roll up long sleeves and not have any restriction in my arms/chest for climbing tops. I also layer a thin merino shirt under my ventus/boreas for cold weather, but 95% of the time they're a first layer.
Rab definitely has a slimmer cut than most Pata. tops, I would say. From reading reviews the Borealis was slimmed down from the Boreas, for what its worth. I'm assuming the Pulse will be fairly loose cut, based on photos, and it being a sun hoody. https://support-us.rab.equipment/hc/en-us/articles/115004360145-Sizing-Guide-Men and maybe try to find some reviews with people who give dimensions and have photos to better estimate fit - good luck! Once you find your fit, keep an eye out for sales/ebay - Rab isn't popular enough in the US, so you can score some great deals.
I got the BD Alpenglow (2018 model) recently & I've used it the past two weekends in Yosemite when it was high 80s & sunny. It kept me from getting burnt & I was relatively cool (as cool as you can be in 80s & sun). I also used it on a few Off-widths & Chimneys and it seems to be holding up well. It stinks right now...but I also chimney'd through a wall covered with bird shirt plus I sweat a bunch. So can't really blame that on the hoody. The hood is a bit big which at the belay's is nice because it hangs over my face to protect from the sun. But it can get annoying when it falls over my face while climbing.
I ended up buying the Bight Gear Solstice Graphene. I absolutely love it! I'm the guy who burns almost immediately but I wore it kayaking and I was completely protected. Breathes well, dried quickly, just the right amount of stretch, and it seems durable enough to climb in (Haven't done it yet though). Hoods a bit big if you wear it without a helmet/hat but its definitely doable.
But truthfully the fit is fantastic compared to the other sun hoodys I've tried on. I'm 6' 155lbs with a couple points on the ape index. So I always struggle with mediums not having enough sleeve length and larges being too baggy around the chest. But the medium fits me perfectly! My GF was laughing at how stoked I was about it, but as a person who burns easily/has sizing issues this was a game changer. I'll definitely be picking up a second one in the next few days.