Woah those are great, both the models and the painting. I don't try to paint tanks often so while I can get the flat colour down pretty well the weathering is something I've not really got right yet myself.
I particularly love the sonic tank, anything with a sonic weapon reminds me of playing Dune 2 as a kid as house Atreides with their sonic tanks, great vehicles but if you positioned them badly they did horrific amounts of friendly fire.
The Su-85 packing a railgun and Mantikor on your site are both brilliant too.