I had two BAM50/51, they can be tuned to shoot real well and the triggers aren't half bad. The B50 has a nearly impossible stock, it just isn't designed to fit a human in my opinion. I'm 6' tall and cut a full inch off the stock on my B50 and it was still too bulky. The B51 stock was much better, actually it was great, but if you plan on carrying it in the field you'd better be strong, they are a big gun. With a good tune they can crank out plenty of power in .22 for small game, but they are not powerhouses, wouldn't be my first pick for a hunter. If you go this route talk to Big Ed and get one tuned, it will save you ALOT of heartache, trust me on this. Many of them leak right out of the box and most need a barrel recrown before you see any great accuracy, Big Ed takes all of the risk out of buying a new gun and his tune price is VERY reasonable. I think I paid around $400 for a full tuned B51 shipped, then got a shroud from Mountain Air and was a really happy camper...until I needed to sell so I could buy something else...doh!
The Korean guns are real powerhouses and you get ALOT of gun for what you pay, the downside is that if you get the long gun versions they are really long and pretty heavy too, btw they are also really loud at hunting power and tough to shroud. I had a Sumatra Carbine and it was pretty handy and plenty powerfull, and it's a repeater which is nice for quick followup shots. The Korean guns also have huge air resevoirs and eat air, you aren't going to want to pump them for long, a SCUBA setup would make more sense in for those guns. I didn't care for the triggers on either of my Korean guns, the Sumatra and Career both had triggers designed by lawyers in my opinion, need a strong trigger finger.
DaveD is right about the FX line, I owned a Black Widow that was a really nice gun and have shot Dave's Cyclone. The Cyclone is a sweet gun and there isn't much to not like except maybe the price and the synthetic stock. The build quality on the FX guns is top notch. I think Gene really likes his Cyclone as well:)
Never owned a Daystate, want one real bad though, but Gene is right, they are really pretty to be carrying through the brush....don't think they make the Huntsman anymore btw, but I see them on the classifieds over on the Yellow every so often.
Had an Airforce TalonSS and for power they are pretty tough to beat except by the Korean guns. The triggers are mushy, but with some work can be made "ok". The real setback with those guns (Talon, SS, Condor alike) is the tank/stock. Using the bottle as the stock equates to a really high comb which tends to make your neck bend like a giraffe to shoot it (thing gave me a heck of a headache). I loved to tinker with my SS, but at some point I just wanted to shoot and decided to sell it so I could shoot more and tinker less. They shoot ok out of the box, but really need a bit of work to reach their full potential. They are US made though, right here in Fort Worth TX actually:)
Never shot a Disco, but doesn't look like a bad deal for someone just wanting to put one foot in the water with PCP's.
I already expressed my feelings towards the Air Arms guns above, I think they are a great bang for your buck. I've seen used guns from $500 for a single shot S400 upto $650 for a multishot S410, if you buy new they are quite a bit more expensive, and the newer side lever actions will run more even used. I paid $500 shipped for my S400 carbine 12fpe gun, but I see FAC guns going for the same price if you watch the classifieds long enough. I also have an Air Arms S200 which I really like, but it is also a 12fpe gun and doesn't have much power for hunting more than real small game.
I know little or nothing about the BSA PCP guns except that I shot a Super10 once which seemed like a nice gun, although they all seem to have really high fill pressures...., but I don't know if a lower fill upsets their performance at all. Most people that own them really like them, I had a BSA Superstar and the build quality of that gun was top notch, so I would suppose the build would carry on with their PCP's.
Lots of stuff to think about, and honestly there is no "perfect gun", there's just guns that are good for one thing or another. We could all go around and around saying which gun is the best, but really the best gun is the one you want the most at the time:)