Well we can all agree to disagree or keep swinging our purses at each other.
I went with torflex, because its not a bouncey stock trailer spring axle setup. Yes I could have gone to different springs and shocks, but that is not off the shelf, its semi custom. Yes I know parts are not hard to get, but what spring do I want, one from a jeep, one from a chevy s10? Its not like there is a ton of info out there, there is info but I have never seen a list that says if your trailer weighs this, and you want this length spring get this spring from this vehicle.
Torflex is off the shelf so is timbren and I was thinking about both.
Why does one of the trailer axle companies not make an independent swing arm set up using coil springs. Easy to customize just by saying use X spring for Y weight. Set it up with shocks and everything, make it bolt or weld on. Oh because it would cost even more, restrict frame design even more, and never be perfect just like every other system out now ( as in no system is perfect now ).
The biggest design issue with the swing arm is the normal two frame members we are used to attaching axles to are not what it mounts to. you need a big heavy duty cross member very solidly attached to the frame members.