i like this tire but want to keep the weight down, but scard that the single ply side wall is too thin and i will cut the side out of it....
My advice: if you'll be doing true DH runs on this tire, don't worry about the weight. It's more important to be able to get to the bottom of the hill.
If this tire is intended for more aggressive AM riding, go with the single ply 2.5 with Exo-Protection. The weight is roughly 845 grams, and it rolls much faster than the dual ply DH version. The Exo-Protection is extremely tough, so you shouldn't worry about sidewall cuts.
The 2.35 might be a little small for the stated size but certainly NOT a 2.1! unless you're comparing to Nevegals which are oversized. In fact the 2.35 DHF's are bigger than many 2.35 offerings from other makers including Hutchinson and Michelin so I have to laugh at all this 2.1 talk.
"There's two shuttles, one to the top and one to the hospital" I LOVE this place!!!