Plain and simple they are all good to go, best bet is to see if a local range has them and rent and shoot, the ergonomics are a tad different on them but you find it doesn't matter to some.
Remember if your are not going to be the only shooter to take along your partner to try all so.
As to 9mm too many people play the calibere game and worry about what round will work or not. The 9mm with HOLLOW POINT rounds if legal in your area will do every thing that a 45 or 40 will.
I have carried them all and have had them issued,don't get hung up on departments changing to another calibere, majority still caryy 9mm, they change due to politics and piss poor shooting by the average cop .
Pick your poison and PRACTICE! Shot placement is the key and 9mm for that is cheaper at this point then 45
As my mentor Mr. Bryce was fond of saying "more holes in ,more blood out"