So I'm thinking of upgrading from a Line 6 POD STUDIO GX, to something that can do more, like record microphones, but then I remembered the KB37.

Can I use the KB37 as a midi controller for my "virtual pedals" and effects?
I play some keyboard and I could probably use this very nicely.
The KB37 also has an expression pedal input apparently.

I'm edging near 800 dollars though, because I'm buying a shure SM57, expression pedal, a Marshall MS-2 for playing on the go, guitar strap, mic stand, and other crap.

Is the extra approx 100 dollars worth it? I don't want to buy an UX2 and then suddenly say "hmm I wanna play keyboard stuff now"
May I ask why you want to upgrade? :] And what the Pod Studio GX is like?
The Pod Studio is great for recording guitars, but I should have gotten more money and just gotten a UX2 instead probably, because now I'm looking to get a shure sm57 for vocals and cab recording.

Now I want to get a KB37 instead now that I think about it because I like to play some keyboard, and KB87 has midi controls so I can do midi learning on the effects and all.