Porting might be a consideration too. The PSW10 is front firing and front ported, so as long as it doesn't have anything obstructing the front of the speaker you should be fine. If you ever upgrade (I have a PSW10, and love it. But with your setup, you could definitely use some more power to balance with everything else) just take into account the design of the speaker. Sealed units, like Definitive Technology's, will be the best for placing inside cabinets. I would also stick to front firing. You could also get away with down firing, as long as you've got room to let it "breathe" behind the cabinet.
If you're going to be setting it on the base of the cabinet (ie on wood, instead of carpet et al), just make sure you do your best to decouple the sub from the cabinet. Use the rubber feet on the the PSW10. Auralex actually makes pad specifically designed to isolate subs from whatever they're sitting on. Links below.
Post some pics when you're finished!
http://www.swee****er.com/store/detail/SubDude/
http://www.auralex.com/sound_isolati...de/subdude.asp