" I tried using VPIs stainless steel screw down clamp with rubber gasket, but I don't find it performing any better than HRX weight with warped records"
dmk_hifi - the amount of dish provided by the clamp/washer is limited by the degree/area of warp the LP has.
I play used LP almost exclusively. I don't play LP's beyond what the clamp will fix.
A slightly thicker washer (for more dish) MIGHT help for those?
There are some less costly than VPI periphery ring solutions. None of Agon at the moment.