Speaking of wear and tear on the hucard slot I have two white pc engines. One of them works fine with the IFU the other doesn't. So my plan is to keep the turbo everdrive in the non IFU working one and the system card 3.0 in the IFU compatible one. Problem solved, don't have to worry about those teeny pins getting bent out of shape.
On the other hand, friction is nature's contact cleaner. The easiest way to fix a dirty, crackling connection on a patchbay or audio mixer is often by running a plug in and out of the jack a couple dozen times; the same principle applies to cartridges. Stuff likes to get used. When neglected, rubber tires crack, oil congeals, gasoline gets shitty, muscles atrophy, Duo memory banks vanish, and metal corrodes and tarnishes. I left a N64 memory pak in a controller for ten years and it seems the contacts fused and/or tarnished together - the memory pak no longer works in any other controller and the controller can no longer read any other memory paks.
The best bet is to use ALL of your...*ahem*
hucard slots fairly often, but use a cheap system for your everyday workhorse.
Finally, I suspect half of the "worn-out" hucard slots reported are really just dirty. Turbo users are pretty blasé about system cleaning because our decks have never had a big problem with dirt and very few TG system cleaners were ever made, but they do need cleaning occasionally.