Short Tube Exhaust question

Hey I need a new h-pipe and was looking at my options. I am looking at street legal ones and trying to decide between Magnaflows X-pipe, Bassanis x or Mac's h-pipe. I think I would go with the Magnaflow but my question is has everyone experienced the cats being lower that the stock placement cause that would be too low on my car. From what I've heard they are going to be 3/4 inch lower, is this true. Thanks for any help.