I thought RTT's could keep all the bedding in it! That would be a bummer. Are there any RTT's that let you keep the bedding in it? We thought about getting one on top of the camper for the kids. To help reduce setup time of their stuff, we picked up a couple of instant pop-ups. It's going to take long enough to get the hooligans to clean their crap out of them and was thinking a RTT would be faster, if we could leave the bedding in.
I raised it solely for rig alignment with the hitch, so not enough lift. As far as I can tell there's no such thing as an articulating drop hitch, so adding a level of 3" square tube at the axles lifted it just enough to keep it all right in line. (Into a 3" lifted 4Runner.)
No springs for me. I sprung for the 3,500 lb Timbren Axle-less system with brakes. (I think maybe the 3,500 lbs is how much they weight...
) Don't really need that much capacity but it's there if I want it and I didn't want to go without brakes. And that's the lowest rating to allow for brakes.
Your helper springs look a lot like a diesel heater.
(sarcasm is the language of my people)