MPC 2500 user here.
I recently restored mine after decades of abuse. highly recommend the right side smooth jog wheel/PCB mod, improves the feel of the machine significantly. - no more sticky tack switch syndrome and feels way better. certain parts of these machines aren’t built that well imo. also recently replaced the pad sensor as I had one dead spot and added an SD card mount. I think you can go up to 100 GB memory. thinking about buying a skin next as my case looks water damaged due to years of use. would anyone recommend this?
I would really like to do the battery mod, but seems like the kits are sold out?!?