Yes, IMHO it would be OK - lots of performers (including me sometimes) work that way. The drawback is that you must remain very 'static' whilst performing so that the guitar sound doesn't drift away. I've know a lot of people who are static when they're performing! :-)

As withg all these things, you're very much in the sound-guy's hands with regard to what kind of sound you get, but that also applies if you have a pickup/transducer fitted.