This one is super. I originally bought the little brother, GP-5, which is awesome but when this came out I immediately got it. Stereo out, expression, midi, looper, on hardware chain editing and control... These are just a few of the new features. I need to say that I never thought I would use it without plugging it but yes it has a 1450mA battery and I use it all the time. Now we still have small issues like, we cannot use the nam and the cab IR at the same time. Of course, for the price, we don't even need to care as far as I am concerned cause this is not great at the price point but in general. Comparing to some of the big names, it has kind of a scooped, duller mids sound in similar loads. No matter, highly recommend. Not to mention you can get two and get two rig-stereo, automate it via midi and even use it as an interface.