Definitely try them out for yourself at home. The Studio 20 v.3 is one of the best speakers in its price class that I've heard, and has particular strengths in how it images and projects a big soundstage. Very impressive overall speaker.

When I was auditioning speakers a few years, the previous versions of these speakers were among my finalists. The 600 series overall had a more balanced sound, but it was also less involving with home theater sources, which is why I opted for the Studios.

These S3s are voiced somewhat differently than the previous versions that I heard, so that might have changed. However, the 20 v.3 versions are now better balanced than before, but still retain the involving character that I appreciated with the v.2 series (which I own) while adding a noticeable improvement in the imaging and ability to "disappear", which were already strengths to begin with. Like I said, try it for yourself. When I auditioned the two series for myself, the choice was pretty obvious for my preferences.

As far as the center channels go, definitely take a careful listen and make sure that the levels are matched as closely as possible. And if you plan to add surround speakers, take a good listen to those as well, because the quality of the ancillary speakers can vary a lot from manufacturer to manufacturer. The new Studio v.3 center speakers are a good timbre match for the mains and use identical drivers to the rest of the Studio series. In general, Paradigm has done a good job making center and surround speakers that are up to the quality of their mains, and can voice match them. The surround speakers in particular give you a good option between the dipolar surrounds or going with another set of direct firing bookshelf speakers.

B&W has had some missteps with their ancillary speakers, so I would watch out for which center and surround models you opt for. With the previous 600 series, their lower priced center speaker model was a less than adequate match for the mains, and the dipolar surround speakers were even worse. If you prefer dipolar surrounds, I'm not altogether sure that B&W's current surrounds improved upon the previous versions by much. If you go with B&W, you're probably better off going with another set of direct firing bookshelf speakers.