Removal and replacement of the subframe is pretty straightforward. Are you going with an aftermarket subframe?
As for subframe connectors, I am happy with Global West. They really hug the bottom of the car, the weld in the rear and bolt in the front should you need to remove your subframe again. I think some diehard drag guys will say that they prefer full weld-in connectors. If you want the welded ones, I would recommend Detroit Speed & Engineering's (but you have to cut your floor).
Here are my Global Wests:
The contour to the bottom of the car, about 1/2" off the floor pans. The fit is excellent.
Phil