I need to add some help to the rear springs of my truck as i recently discovered I have been going over the load capacity when towing my boat. Yes, air bags would be really nice, but I dont want to spend the money right now. i had been looking into super springs as a fairly inexpensive and easy solution, but then I stumbled onto the Timbren kit that looks to work just as well and is almost half the price of super springs. Anyone have experience with these? Is the timbren kit total crap or pretty good?