Not necessarily give upone or the other, but don't mix the two. If you have another car, use that. If not, and you go with your dad or a friend, offer to drive for them. I think a golf bag has more chance of fitting in an RT rather than a GTS, the GTS has the cutout for the spare in the back, but doesn't look wide enough for your drivers (maybe). Check out the link, I think the angle of the pic makes the hatch look bigger.
GTS hatch with Snake-Oyl tapestry mat
In the trunk of the RT, you can angle the clubs in. As you can tell, not many hear use their snakes for cruising or carrying stuff, other than heart-racing passengers.