SoundSplinter RL-P vs ID MAX with 800wrms

[Joe Smoe]

I know millions of people ask questions like this, and it gets annoying, but I've gotten my list down to two subs:

ID MAX 12"
SoundSplinter RL-P 15"

I'll be pushing whichever sub I get with an Orion HCCA 250g4, wich will give 800-900 wrms at 1 ohm.

With that wattage, which sub would you guys guess will be the loudest? No stupid guesses, I want experienced input from people that know what their talking about. I know the 15" has an advantage because of cone area, but the ID MAX's have pretty high displacement, and can belch out some very high spl numbers if done correctly.