I biked on the highway 77 bridge to get from the MOA to Ironman bike ride start. The nearest non-freeway path I could find was an extra 20 miles, which I would have had to do again at the end. The shoulder is wide, but full of junk. Traffic was light so I can't help you if this is for a commute.
I have no moral problems with it when there is no reasonable alternative. But if I were planning to do it regularly, I would try to get it approved like
some freeways here in CA.