after a 2000 mile RT, towing a 7x14' box for the 2nd 1/2 of the trip in a side wind/ tail wind, I just ordered the 1000 lb black fronts to replace the 500 lb blues.
if anybody is looking to buy sumo springs there is a 15% off discount at manufacture website supersprings.com using code workfromhome.
This was cheaper than anywhere else, and it has free shipping and no tax