Think they can help with some extra quad strength. However don't see them as important to improve a general back squat. Even less so for a lower bar 'powerlifter' squat, but then I think don't think any other lift is either.
Fronties are a good all round strength lift still. Lots of power and leg strength needed plus taxing around the mid section and upper back.
Cus smoking and tripping is all that you do. Ohhhh yeaahhh