I own the MRS-8 and love it. I can definitely recommend it! It has a built in Rhythm Machine (Drum & Bass), so that would be handy for a guitarist (I turn teh Bass portion off on mine, but have listened to it and it is useful). The internal effects while not great, are also quite useful. The internal condensor Mic is excellent for recording practices, lessons, jams, rehersals, etc... I use mine almost every single day.
Have Fun!