Three gun? I don’t do it. Canik rival. Glock 17L /34 if you can afford a barsto barrel and a non sponge bob trigger. Don’t need mucho roundo’s then Springfield range officer or above 9mm. Cz shadow.
bullseye? (no one bullseye any more) have a CMP rem rand frame colt slide with hours of custom work and fitting I picked up at a ghetto gun store long ago for a great price. Sometimes even a pig finds a go lden egg in the hood. It only took about 7 minutes to examine and pay for it.
Silly wet? ( No one silly wets any more) my browning buckmark silly wet, or my contenders.
There is no best. As others have already mentioned, we need to know what kind of competition. USPSA will be a little different than Cowboy Action, which will be a little different from Bullseye, which will be a little different than Pin Shoots, which, etc., etc.
OP, if you go to the Shooting Sport section here you'll see a white paper posted on Shooting Competition, it does an excellent job providing an overview. You'll find if you ask specific questions, you'll get lots of help. We just don't know which way to point you since your question is so general.
I choose a different handgun for local competitions every few years, and my current Walther PDP may change that. For me, and for the kind of shooting I do, the PDP has been the best out of the box pistol to date... I might just have to stop this endless cycle.
Saying competition is a very broad term.. are we talking uspsa, cowboy action shooting? Or what? I got my start in uspsa with a Glock 34 and loved it. Ended up switching to a p320 legion and loved that.
Put a lot of rounds through a couple of different Canik TP9 series guns at matches. Never fail to run great. The latest Mete line has a better optics cut that keeps the rear sight, and the Pro version of those has their better flat face trigger.