I used to say I'd never own a Ruger...
... and I voted for the Ruger P90.
I was fortunate enough to get a chance to shoot a P90 recently. The Ruger P90, IMHO, seems somewhat similar to a Sig P220... How? I don't exactly know. Maybe it was the "point-ability" of it. I often joke that my Sig P220 points itself, and I just pull the trigger. The Ruger P90 feels the exact same way, and was very accurate. The recoil was a little more stout from a P90 than a Sig P220, but the recoil just made it more fun to shoot. I'm sure it's because the P90 is lighter, but it was still very pleasant to shoot .45ACP from - just a tad different than a Sig or a 1911. The trigger was nice on the Ruger as well.
FWIW, my friend who owns the Ruger came here to learn to clean it, field strip it, etc. He'd owned it for quite a while, but didn't get a manual with it, and hadn't learned to clean it in the couple years he'd owned it. A couple patches and some Hoppe's #9 made that gun look brand new, and it functioned just as flawlessly.
The P90 was my vote because it's a .45ACP, and a good gun to shoot that round from. Very rugged, reliable, and accurate weapon. Personally, I would choose a .45ACP over a 9mm Para (9x19) or Kurz (.380acp) anyday. I just don't have the same faith in .380 and 9mm that I used to.
FWIW, I own a Beretta, and have owned several in the past. They're great guns, just boring to me. CZ's have a fine reputation, I have no experience with them as of yet. I trust the good folks here at THR, and have heard enough good about them to feel comfortable buying one. If I got a Bersa Thunder, it would be the .45. I hate everything about Kel-Tec pistols, but that's just my very biased opinion. I've also heard about more reliability issues with Kel-Tec than any other gun in your poll.
You choose whatever you like best. None of us can tell you how the gun will feel in your hand, point, fire, or function for you. I'd recommend going to a range and seeing if you can actually shoot some of them before you buy them. Good luck with whatever you choose!