That's certainly something to consider.
When you install a sunroof, you compromise the structural integrity of the car (to a certain degree). With this comes more body flex, right?
I think this may be why t-tops have such a propensity to leak.
On the good side, most manufacturers now offer a lifetime leak warranty, and the seals/gaskets are made with high-quality rubber. It won't dry out and crack like the old-school sunroofs.
1996 Mercury Cougar XR7
4.6 - Dynomax-Equipped - Tranny Cooler - 3.27 T/L - 125k Miles