The warrior/falcon/asena guns are made in turkey and are usually almost identical to other brands also made in turkey (ex, hatsan, weatherby, etc), but with a few cosmetic changes requested by Martin at corwin.
What are your plans to use the gun? If you're thinking of duck hunting, the falcon or warrior will likely be a better fit, and then it comes down to if you want a gas semi (warrior) or kinetic(falcon).
Personally i have only ever used gas semi's, so i can't comment on how they work vs a gas semi, but there's lots of articles out there comparing them.
I like the asena, but it's not going to make the best hunting shotgun. I think i would be great as a slug gun, but the ghost ring sights don't (for me anyway) work as well as a bead for wing shooting.
The asena is a bit heavier than i was expecting based on the warrior shotguns i have held, but it's good heavy, feels really well built, and mine cycled low power target rounds right out of the box, but for the type of hunting i typically do with a 20ga i do more walking through brush than actual shooting, so a nice light break action if where i go to. I found the pistol grip stocks that they sell for these make it much more comfortable to shoot and carry, and they felt much better quality than the tapco stuff i have held on other guns.
All in all i've had great service from Martin at corwin, any issues i have had were fixed immediately and i don't hesitate to recommend them to anyone.