I'm a big fan of most of the shorts that TLD puts out. The stretch that they provide in their materials, while still keeping durability a factor, is top notch. I ride these and the SKyline shorts(no chamois) and i will say that the undershort chamois in the Ace shorts is money in the bank. The distal(knee) end of the chamois liner is THE most comfortable leg closure that I have found on a trail short. Many shorts provide a rubber stopper on the inside of the leg end, but these have a silky smooth lightweight stretch material that allows for range of motion, not too tight of a feel over longs rides and still the ability to have the chamois stay in place. I much prefer this to any rubber component down my my knees.
The vents are great, the Velcro closure on the crotch is alright, but a lightweight zipper might have been a better option for a $140 pair of shorts.