I just picked up a Giant STP1. It feels solid. Handles, shifts and breaks accuratley and isn't even that bad on the street.
I admit I am a noob, and don't really know about the different makes and components.
Is the STP line even comparable to the ones mentioned in the orignial post. Or is Giant a mass market bike store type brand?
Anyway, I have had mine out a few times on trails and just screwing around and not only have I found no faults yet, I actually and happier with it each time I take it out.
Just my $ .02