Dave if you wanted a HSS lock miter bit you would have to have it specially made. Lock miter bits come in at least 3 sizes for different thicknesses of wood. Make sure you get the one for the range you want to work in. Infinity sells a set up gauge for around $35 I think that works for different thicknesses of wood. I know that CMT's online catalog has a small section in it showing how to set up some of their more difficult bits like rail and stile and lock miters.
In a bit test about 8 years ago Infinity rated better than CMT, Amana, and Freud but not better than Whiteside or Eagle America. Freud bits are good but I don't have the same love affair with them that others do. I have had better performance out of my Lee Valley bits and, in fact, Lee Valley also scored higher than Freud, CMT, and Amana in that bit test.
Someone I consider a master woodworker once told me that a master woodworker is not someone who never makes mistakes. He is someone who is able to cover them up so that no one can tell.