I have a 2010 E350 with the karmon speaker system, owned from 80k miles to currently almost hitting 200,000 miles it’s been dead reliable, only issues I’ve experienced were worn out motor mounts, trans mounts. When changing the accessories pulleys due to high mileage I forgot to change tensioner pulley causing my serpentine belt to grenade itself twice

I saw it's selling

Don’t shut the boot like that, it has soft close, just shut it gently