I have the JS-8 but I absolutely love it. I bought it about 5 minutes before Boss came out with the JS-10 but have not regretted my purchase for one second. I've got a Fender Blues Jr. but it has been weeks since I have used it. I use the Boss 90% of the time.

It sounds silly, but for me the main thing I use it for is practicing with headphones early in the morning so I don't wake my wife.

But it is awesome. I move stuff I am working on to a thumbdrive and then move it to my Boss with that. You can plug it into your computer as it will be recognized as a drive but I've never had the need. I haven't dented the storage on my USB or the SD card in the Boss.

You're correct it comes with a lot of awesome backing tracks.

And you can slow down and loop and we haven't touched the surface of all this thing will do. We haven't talked about all the effects you can apply.

Great, great tool.