I've had seven of them plugged in 24/7 for 8-10 years with no issues. Yours is the first one I've heard of going bad, I'm sure there must be others. I don't worry about it.
Did some more digging on what endurance means. I guess this is the rated lifespan when the capacitor is operating at max temp and ripple current. Supposedly a rule of thumb is for every 10 deg C drop in operating current, lifespan increases by a factor of 2. So if my cap is rated at 7000 hours at 105C, a drop to 95C would increase lifespan to 14000 hours, still not all that great. I think I will unplug my modded MPCs when not in use.