This is a touchy area. I bought a used 150 that came with version 2.5, and I wanted to update it, as well as reverting to the factory default presets. It failed spectacularly, even when trying to do it while a Line 6 tech talked me through repeated attempts on the phone. I'm very knowledgeable computer & hardware guy, and tried it with 3 separate desktops. It left me without a functioning amp, which had to be sent back to the factory to take care of it. Line 6 was gracious enough to make the upgrade at no charge, but it cost me over $110 to ship it to them. That sucked the heck out of the good buy that I got in selecting a used device...