Shoulder holsters are...great to look at, but lousy for actually carrying a gun.
I tried Alessi, Jackass Leather, Galco, you name it. None of them really worked. In my opinion, even the "perfect" shoulder holster is still a "compromise on purse strings". There are seventeen ways to sunday in which your draw can be impeded, even if no one is tying to impede your draw. Your seatbelt shoulder harness is one heck of an opponent at times.
My STRONG prefersnce is a GOOD OWB or IWB made for strong side carry. Good leather, wide belt slots, make for good retention, and really good concealment.