I'm a "big tagger", and I have no problem with it. I don't control the type of traffic going through it, though; from my understanding, TCP/UDP wouldn't make much of a difference?
All the Flex swithes I tried glitched: USW-Flex-Mini, USW-Flex-2.5G-5 (frame drops and interface going down for several seconds) and (to lesser extent, just frame drops) USW-Flex.
Have no idea why but I observed that more under UDP loads.