I found it interesting… Quite succesfully gamified practice and got me out of a long rut, much like you describe. You absolutely need to have songs you want to play so I ended up buying a fair amount of DLC (not sure how that works now, they included a load more stuff with the pc version after a while)
Buuuut, I found it a bit flawed. I’m a reasonable guitarist, not good nor terrible but a lot of songs had sudden huge hikes in difficulty- they start out with a stripped down version of the song then add in complexity/accuracy but a pretty high proportion went from “no bother” to “frustrating” in one jump, and the interface isn’t great so rewinding or trying parts over and over is way harder than it should be.
Likewise with the modelling- now to be fair, I have a good modelling amp so I’m a harsh judge but the issue for me was just that tweaking things was too clanky to be fun- I never found myself thinking “let’s throw some noises together and see what happens” like I do with my Vox.
It’s a very clever toy though, and I do like it. I don’t think it was really that succesful as a sole tuition device but that’s not really what I wanted from it anyway