My personal experience with TCs is limited but for many many years I have been hauling loads and gooseneck trailers. So my personal experience on products that help with load carrying is:
I do not like helper springs or additional springs if you will ever drive unloaded. It will have a horrid ride. It will be great when loaded though.
I have tried the Hellwig helper springs and Roadmaster RAS helper springs. Both were removed and reluctantly given away. I say reluctantly because I think they rode so bad I didn't want to anyone else to go through that.
I wish I'd have found Torklift's Load Stabilizers sooner. They help engage that lower overload spring sooner so it doesn't squat so far before it starts helping. It's such an obvious idea and it works.
I've never used Timbrens. I probably never will.
After using two different brands of airbags, I finally found some I like. Air Lift bags with the internal jounce bumper. You can run these things with no air pressure when unloaded. Perfect for me.
