Rob, those guides are formed specifically for Oregon chain (even if it doesn't have the Husky sideplates). They'll work very well for Stihl chain after some simple modifications - I know 'cause I've done it. I'm sure the same can be said for other brands of chain as well (what else really <i>is</i> there anymore, maybe just Carlton?). I bring this up only because you didn't say what you were using them on.
With the Stihl chain, not only will the hook differ greatly from optimum as the tooth is worked back, but the pitch is just slightly too great on the pre-stretched chain even when new, and the guide will lift either the front or rear rivet on the cutter when pressed firmly into place. The differing top plate angle of the chain causes the first problem, but at least it's consistent. The second problem is maddeningly variable. Both remedies are fairly simple, but then the modified guides are no longer suitable for Oregon stuff.
I use the roller guides to right things if/when I get a bit out of kilter.
Glen