I am currently running e46 M3 transmission mounts which were a subtle improvement with no real NVH penalty. I recently had an ECS tuning order and decided to give the UUC black isolated mounts a try, since i was ordering from there anyway.
Nothing wrong with the M3 mounts, just had an ECS tuning order and threw these ones in to try out. Can see the E46 moutns are hourglass shaped while the UUC ones are cylinderical.
Build quality of the new mounts is average at best comapred to OEM, but at least these ones are properly isolated unlike the previous UUC mounts which basicially had a bolt running all the way through the rubber internally.
Wasn't expecting any difference but have felt that the gearshift feels more solid, would probably feel like a massive difference from stock. NVH is fine, cannot really tell much difference in noise from before, could be slightly louder but its so minor its a non issue.
EDIT: These actually noticeably increase the NVH, more road noise, slight gearwhine until the mounts settle down after a few k kms. More Dual mass flywheel noise. It is noticeable but in no way intrusive or bad.