If you think you might like to struggle up off-widths, this is a good place to start. Duchess Right (aka "Crack Kills" among my friends and I) features 10-20 feet (depending on how early you exit onto the face to the right) of classic 5.7 off-width. As a bonus, it's easily TR'd. Bust out that #6 Friend and go for it.
Protection
Wide stuff. Long slings for belay. A well-placed anchor will allow you to TR this, Duchess, and Duchess Left.
Beauty route. I used small aliens near the bottom crux, and a little heel-toe action to climb through this section. If you want a fun challenge at the grade, give it a go.
I don't know if this is what 5.7 off-width feels like, as it was one of the first off-widths I've done that's more than one move. It kicked my ass. At the crux, the rock inside the crack is like butter and there's nothing on the face until you make a couple of moves. I fell a number of times seconding this, and am pretty confident leading at Josh on 5.7 crack and face climbs like Mentalphysics and Life's a Bitch. I'd have been in real trouble if I'd tried to lead this one!
Take big gear. One #5 Camalot is not enough, and probably would be good to have a #6 or two. Or TR after climbing Duchess.