How old are you? I ask that question because when you get older to start to reconsider your philosophy.
i used to do free weight for everything until I tore my labrum and that happened after I turned 30. When I recovered, I realized that it wasn't worth the risk of injury so I started doing smith machine and i still get the same feel.....i think even better because i don't have to balance the weight.
IMHO, I think the DB's are the best for shoulder work, simple reason you get more free range of motion. When using the BB, the arms are locked, and with the Smith, the pressing path is locked.
If you always use DB's and BB's, I believe you will strengthen the tendons and stabilizing muscles in a way that is hard to do with Smith machines and other equipment.
Not to say that there is no place for certain excersises.
YIP
Zack