Why are you thinking about one? I notice you're asking about T-Top bags. Do you think you'll need luggage space for touring?
I do actually like the look of a rack, and if you do plan on some more serious touring one would be very handy (precious little luggage space in the pre-78 Vettes!), although I'm still not convinced about strapping the T-tops to the rack, even though the kit to do that is available. But as you say, once you commit, there is no going back! I'd say think hard about why you want it.