Radflo 2.5 rear spring questions

[nytefog]

I have Radflo's 2.5 lift kit and wanted to know if anyone else with this kit and 700 lbs front coil over springs if you used different rear springs then the ones that came with Radflo's kit. I do keep weight in the rear and just don't want the rear sagging.

What setups has anyone else used while also using front 700 lbs springs vs the 600 lbs that come with the kit?

Thanks