I've been using Endura's MT500 shorts for over 10 years (not the same pair). I recently bought a pair of the latest version, the ones with the gray panel, and have found that after a few hours of use I get a hot itchy feeling across my leg where the leg gripper runs. Pulling the short up to see what is going on reveals a red rash that follows the line of the leg gripper along with sizable blisters.
I have never had a problem with the older versions of the MT500. The main difference that I can see is that the older version had a more "distributed" leg gripper that consisted of about 3 narrow wiggly lines of gripper. The new shorts have a single thick line of leg gripper.
Anyone had any similar experiences?
Sounds like you had an allergic reaction to the type of rubber used. A female friend had a similar problem with some of those "hold ups" tights, which have a rubber strip around the top to keep them up. I'd suggest either putting a bit of talc on them before use to keep them off your skin slightly, a thin strip of Tubigrip round your thigh (a bit fiddly) or getting some different liners. 😕