I've used a lot of stuff after it was totally worn out.
I replaced the helmet pads in my Bell Sweep, and it was like getting a new one. I even glued the old pads together a few times. New ones were about $5.00. duh
As far as insoles go, I like the Specialized blue ones. They seem to really hold their shape, but I'd replace them immediately, if they started to fail.
S