I have had the Dynomax kit for a bout 6 months. I was checking my ujoints when I noticed a lot of discoloration on my exhaust system where is clamped together with the supplied muffler clamps. So, obviously an exhaust leak. Anybody use bandclamps instead? do they seal the exhaust very well? i could get the system welded, but I would rather use band clamps so I can replace the mufflers and pipe sections myself if need be. Plus cost is probably about the same. How do the band clamps seal? do they use some sort of rubber seal inside the band?