While some people have had problems where the bearings or guides have worn out it’s usually just that it’s developed play and needs adjusting. Especially if you’re doing a lot of cnc work. I’ve had to adjust mine a couple times in the 2 1/2 years I’ve had my 350. The procedure is fairly easy and doesn’t take very long. Most of the work is in disassembling the machine itself (especially getting to the y-axis) which you’d have to do to swap out modules anyway. The only tricky and delicate part is the limit switch.