i have a feeling i am using the 2.1 but could be wrong
anyway i used it for 9 months last summer/winter never had a single puncture, changed to a set of cross marks the start of this summer because god they roll slow, loved the cross marks for speed but within 10 rides i had a few punctures, so set them up tubeless then 2 rides later slit a side wall.
put the lusts back on and since i have (5 months) have not had a single flat ( now running tubeless)
there is a weight penalty there really heavy and roll really slow, but are very strong imo