They'd all be pretty scary to fight, regardless of how much training you have. If Maia gets you anywhere near the floor, you're toast. The gap between his jiu jitsu and yours is far greater than the gap between your striking and his. If Askren gets on top of you, you're glued to the ground and will be miserable until he feels like letting you up. Nate would be absolutely TERRIFYING to fight, though. Sure, he's not very scary in the conventional sense, but I think just knowing that I'm fighting a guy who will not get tired and is practically impervious to physical damage would absolutely be in my head. Because you know that you can hit Nate with damn near everything and he'll still be there and on top of that, since you'd still be completely green to the sport, you have no clue how your gas tank would hold up in an actual fight. If the first round is over and you're already winded, you're absolutely fucked against that guy haha. There are fighters who don't deal well with getting drug into deep waters. Nate Diaz lives underwater lmao. Good luck A. taking him out and B. outlasting him.