Putting aside the various fringe and protest candidates, if I'm correct we're basically talking about two plausible nominees right now, Mitt Romney and Rick Perry. (The others matter because they give people a chance to express with views and to influence the course of the party, but they aren't very likely to be nominated).
So whatever you might do in the primary, you're probably voting for one of those guys next November. And I'm sure you'll do so believing that he'll be better than Barack Obama, given that either will promise and deliver far more conservative policies than Obama will (in which by conservative I mean policies supported by mainstream Republican conservatives, of course). So that's not my question.
My question would be: do you have some reasonable confidence that you'll be voting for someone who will be skilled at the sort of things that presidents do? Or, to put it another way...the party's job is to nominate someone who (1) supports party policies and (2) is well-equipped to be a good president. Do you think the Republican Party is doing that job well?