I'm just splitting hairs, I like to obsess.

Best thing is to try it both ways. As an experiment I'd do the following steps:

a) set the 950 w/ main speakers as small and a 40Hz crossover. Connect your source and run the outlaw in stereo mode.

b) set the 950 w/ main speakers as large and play the same tracks again this time w/ the 950 in "stereo bypass" mode. Notice if you are missing any low bass. Notice if the midrange and highs are a little more "clear" with less "grain" and have a better dynamic now.

If you find that you're missing a little bass but prefer the sound of your source's DACs over the Outlaw's DACs, you'll want to get an ICBM or other high-quality crossover, like a marchard unit or the NHT X-2 (as around on audiocircles, there are a few users over there using other external crossovers).