The .45ACP is my favorite handgun caliber, both for defense and practice.
While I don't much buy into the "9mm vs. .45" debates, every little bit of increased bullet size and weight helps, assuming first that you hit accurately and that you hit something that counts!
I've carried my 1911s "cocked and locked" for 20 years.
If you have a thoroughly-reliable example which has been gone over by a trained, practical, experienced 'smith, there's no overall-better choice in a .45ACP sidearm, IMNSHO.
OTOH, there are alternatives which I do carry (Glock 36, Glock 30) and have carried in the past (Sig Sauer P220, HK USP .45 Compact) and they are certainly viable, for folks who feel insecure about Condition One carry with the 1911, though of course none offers the stellar trigger pull of a "tuned" 1911. (I mean a light, clean, crisp break, not any sort of unsafe trigger pull.)
For those folks who feel they can get along with the DA/SA type of semiautos, I'd suggest unprepared-but-time-dependent drills, wherein your first shot MUST be accurate, must occur within a given short time frame not of your own choice, AND subsequent shots must be made accurately on a target that's now moving.
This will unmask just how awful the DA first shot and the subsequent DA-SA transition is on most such guns.
If this seems artificial, consider that it's what happens in a real life defensive situation; you must make an accurate on-demand shot, and may need to follow up with more such on a target which may well now have moved off the original line of fire.
This sort of emphasis, and qualification thereat, is taught by many modern trainers, eg. John Farnam.
Personally, I've never seen a single person who brought a DA/SA auto to one of his classes successfully qualify, which bespeaks the difficulty of using that style of gun. JMNSHO.