639, my common carry arm since the early nineties. Shoulder holster is no problem for carry. I own a 9VE, but much prefer the 639 as the primary carry as it is much more accurate than not only the 9VE, but any other semiautomatic I've ever owned....and I've owned and sold many. It is heavy, no question, but not heavy enough to be a problem. I like carrying one in the pipe with the safety engaged-a simple forward push on the safety and it's rock and roll. I've put literally thousands of rounds through my 639 with 1 stovepipe on a reload. I was so shocked the one time the 639 choked on a round, I put the spent casing in my range bag about 10 years ago where it still remains. I've grown to accept the reality that shot placement is key, not magazine capacity. Simply have not encountered a more accurate 9mm in my experience. Great pistol. If you ran out of rounds, you could easily beat your adversary to death with a 639. Try that with a Glock. Makes a nice anchor, too.