Big difference.
Two different P99 actions.
The P99QA (quick action) is a striker fired semi-cocked double action. 8lb trigger pull through 0.31" (Glock like). No decocker, no safety, though I seem to remember they make some runs with a safety for some LEO procurements.
Then there the P99AS (anti-stress). It's a a true SA/DA. The twist is that it has a mode where the trigger has a very long pull first shot. (0.551" at 4.4#) It's there to help prevent accidental discharge. However, once you fire the first shot then the subsequent ones are a normal single action very short pull (0.31" at same 4.4#). They use the disconnetor to determine where the trigger is set. And you can always take up the slack, leaving it in short SA mode.
The gun has decocker. And then it operates in a true DA mode. Long, heavy pull (.551" at 11#).....for the first shot, then SA from there on out.
There is no "manual" safety. My complaint with this gun is that the reset is very short and I sometimes fire "doubles" when I wasn't meaning to. Takes practice.
The grip, for me is probably somewhere between a single stack 1911 and the double stack PT92. The later I find much to big for my tastes. It does come with extra back straps and I use the smallest. I love mine in .40S&W, but I wouldn't use it in competition. The variation in trigger pull throws me off, plus I'm not sure that some ROs wouldn't make you start decocked. I do like it for my full size carry and bed side gun. Magazines are expensive compared with Glock or XD.