I've been following the Pioneer SP-BS41s since they came out. I was using a nuforce ikon dac/pre/amp with a pair of Infinity P143 speakers, and it sounded fine, but I was never happy with it. When the BS41s dropped to $85 delivered on closeout I jumped on them. I have to say that I'm incredibly impressed with the sound of these speakers. Especially the three dimensional imaging. I feel like I'm in the mix with these speakers. Also, the highs are very smooth - you can listen for hours without fatigue. I find myself listening to much more orchestral music because they just sound so right. They are a very significant improvement over my old Infinity speakers. Really lovely sound.
I have never heard the BS21s, which have a significantly smaller mid/woofer and cabinet. I've heard they have a similar house sound, but don't go as low. If you have a multi-channel amp that will blend with a sub, and a sub, the BS21s may be fine. But if you're going solo with a T-Amp or 2 channel amp, I'd recommend spending the extra for the 41s when they go on sale.
I have them sitting on a desk, and have really been enjoying them.
There are a lot of people around here recommending building your own speakers. I built speakers when I was younger, but they were no match for the kind of careful design that goes into a professionally designed speaker like this. There is more involved than sticking drivers in a box. Unless you really know what you're doing, I would not recommend building your own speakers. Also, If your looking for unnatural sounding speakers that impress for 15 minutes (overly bright), these are not for you. These are best for someone that really loves accurate sounding speakers. Acoustic instruments and voices sound very natural. Given the compromises inherent in this price range, Pioneer really got things right with this speaker.
By the way, I've heard the Daytons, and they are ok for $45. However, they are not in the same league as the Pioneers. Maybe it's not a fair comparison because the Pioneers were retailing for $150-200, but they are getting close in price when on sale for $85. I guess that's technically double the price, but it's a far better speaker in every way. I suspect the BS21s on sale for $50 are a lot better than the Daytons too, but won't have the lows because of the smaller woofer.
Edited by classicalguy - 10/30/12 at 4:36pm