When I went to PP I bought a new HDD and replaced the Mach3 HDD so that I could just swap back if it was not working out. To date I have not fired it back up on Mach3 even once. I highly doubt I ever will. The PP upgrade really is an upgrade, a major one. 100% of the odd un-commanded moves, etc that I had with Mach3 vanished, and I can now drop files directly to the machine over the network. The PP upgrade is a brilliant move on Tormach's part. To anyone thinking about upgrading but not sure, I highly recommend that you do it. If you have cold feet buy a second HDD like I did, unplug the old one and leave it sitting there in case you need to move back for any reason. FYI, I bought an SSD and my boot time from main power switch to refing all three axis is about 34 seconds.

James.