thanks a lot for the compliments guys
BIGGUNDOCTOR, no I have never tested completely to destruction. So far I have tested my knives by cutting paper, cardboard and wood and seeing if it will still shave my arm. Also I jam the tip into a piece of wood and jiggle it around to see if it will curl or chip. If not them I'm pretty happy. All the knives I have made so far are pretty small, so I haven't done any chopping tests with them.
I'm working on a knife at the moment using a piece of coil spring. I'm not sure exactly what type of steel it is, but I'm planning on giving it a good hard test (cutting, chopping, bending) after I heat treat it to see what it can do, and to see (as you say) if I heat treated it properly. Hopefully I'll get some good results :)