Well, thats what I'm going to do...my 15w Dean Markley K20X just isn't cutting it anymore and my brother has a 40w Fender Bass amp he's willing to give me. Should be interesting. After I get my Fuzz pedal built it should rock though.
I've used a 200w guitar cab with a bass head for bass and it worked just fine.. my friend used to use a 65w Ibanez bass amp with a guitar, so I think you'll be just fine.
It is a combo unit, but I figure that the speaker is old and beat (probably) so if I have to replace it with a guitar one, no big deal. Besides, you can't beat free 🙂 I'll post pics of it after thanksgiving when I go get it. It's a pretty cool amp.