SCIZZ,
The two models you are questioning are quite a bit different in price-point at nearly $2K more for the S8's. Having owned and auditioned both these, I will give you my .02 worth.
The B&W 804 (Owned) is a very nice speaker and looks fantastic. It retails for around $3600, but you should be able to get 10-15% off retail. It matches well with separates and receivers....And, they like lots of power! I won't go into explaining how they sound as this should be subjective to your own ears. Hey, if you like them, then buy them.....They are nice, detailed, have great midrange, and matched with a nice sub sound quite impressive. The N803 is more to the pricerange of the S8, though.
The Paradigm S8.....Hmmm, are they really worth 2x the price of the Studio 100v3....Ahh, I'm leaning towards a NO here. If you go on looks alone the S8 completly outshines the Studios and probably the N804 as well. The piano black gloss of the S8 is beautiful, and they have a much, much, much better cabinet than the Studio line and just feel more substantle. The sound is better than the Studio 100v3, but then again, is it 2x the price better? I would lean toward the S8 over the N804 as I think the Paradigms matched with quality components sound better IMO and have more detail. You need more power for the S8 compared to the N804. I would recommend at least 200W/Ch to really made these babies shine. The N804 would also benefit from having more power.
It's your ears, we can't make the decision for you....Both are quality pieces.