I have a Ruger LC9 and don't really like it. Shot a friends glock and found it to be a much better feeling gun to shoot. Never shot a SW 9 but have a SWM&P 40 that I think I'm going to bundle with my Ruger9 and trade for either a glock or Sig.
I would go handle a few pistols at your local gun shop.Maybe find a firing range that lets you rent pistols and shoot a few that fits your hand.
If you're out shopping try to shoot as many of your top choices as you can. Many fine guns have been mentioned here and some of them I own.
Really nothing new to add, I've owned or own various models of all the major brands. All are very reliable and it really does boil down, in my opinion, to personal preferences. My preference was Sig for many years, but our department changed its policy and allowed only G22, 23 and 27, so I learned to like the Glock. Yes it's ugly, clunky etc., but it goes bang every time you pull the trigger and is easy to customize to fit you, so my carry semi-autos are the G23 and G27. My department, like many others, are taking a look at the 9mm, the .40 will still be allowed along side the 9mm models, so the 9mm is gaining popularity and is again considered by many to be sufficiently effective.
As I get older and deeper into retirement however, I find myself carrying a snub J Frame S&W more and more.