Didn't know there was money on this. Or there would be a winner.
Good thing is the OP has gotten some food for thought. Well, it's more like things to try.
The plane he's flying originally came out as a builtup ARF, not a 2.5 pound foamy. And it's powerful enough to do unlimited vertical, pretty much the usual for most 3D models. But it's got an 8 pitch on the sucker. Coming in on final is tricky enough for super light models. Add the overpowerful motor and ANY throttle at all and that speed prop is going to be doing anything but slowing down. 2.5 pounds descending really doesn't create induced drag. So the suggestion was made to try a throttle off landing. An emphasis should be placed on "off".
The winner here will be the OP if the thread actually includes advice that works for him. He's still part of the equation.