Travis M.wrote a review of Scarpa Booster Climbing Shoe - Discontinued Vibram XS Grip on September 29, 2012
Familiarity: I've used it several times
Bought a pair of these a couple weeks back when they were on sale. I guessed on the size as there is no where near me to try on scarpas to get an idea on the size. I wanted to really downsize to a tight fit for hard bouldering and sport. I normally wear a US 9.5 or 10 and got these in a size 8. Needless to say they are very small. I'm not sure if I'm breaking them in or if they are breaking me in. Despite that the I think the fit is pretty good; no airspace in the heel cup and a good curl to the toes. The toe box is set pretty wide which is fortunate for my wide set toes. Overall good fit and still breaking in.
The shoes feel pretty boxy right now and are not very sensitive, but I think that will change as they break in.
As for climbing, they are great. The rubber is super stick (tacky to the touch out of the box). They edge like a dream, and there is plenty of rubber for toe and heel hooks.
My only real con is how stiff the toe box is, but it will loosen up in time.
I would suggest a pair if you're not looking to spend the extra on the new boostics or sportiva solutions