Yes, those are the ones I originally bought (at much higher price because Newegg no longer had them at the time), and my impression is that they sound bass deficient without a sub (combined with Pioneer's sub on sale, it is a really nice 2.1 system in a small room (though I wouldn't recommend for a bedroom system because mine produces a low level hum even in standby), but I like the floorstanders better.
Added the center and very surprised how meaty the bass sounds.
I tested the 41 with a Pioneer VSX-01 and was underwhelmed listening to music. I think something like an NAD integrated or even the Pioneer A-35R might be better if you are focused on music, but if that is primary use, I think I might spend a little more and get bookshelves totally designed for music alone.
For home theater on a budget, it is a great set (51 floorstand front left and right, C21 center, and either the 41 or even another set of 51 as surrounds). The cheaper 21 bookshelves have a different woofer (4 inch) and cut off frequency than rest of the series (which uses 5.25 inch woofer).