Over at toyotanation.com there are a few posts about suspension upgrades. If you are going to change the springs in the TCH, the extra weight distribution is a big deal. The TCH weighs less in the front because the I4+HSD is less than the V6 of the SE. And the back weights more obviously because of the extra battery weight.

Check out this link with photos:
http://www.toyotanation.com/forum/sh...t=TCh+lowering

It looks like what works best right now is a combination of TRD and SE springs. Until a company brings out a TCH specific system.