BOS rock quality is similar to Black Streak, perhaps a bit better. There is much less rubble schwag terrain to deal with. Haven't done Western Hardman, but it seems to be as good or better in terms of rock quality. I think the grading is comparable. BOS is maybe similar to Horns in difficulty. The crux is short but there are extended sections of 5.8-5.10a, i.e. the climbing is more consistent at its grade, hence a bit better.