Does anyone have much experience using 300s as a stereo pair? I was thinking of using them with a Sub for music. Reviews I've seen range from excellent to poor imaging and a "sonic mess" for stereo. I guess that's because the drivers point in all directions. Other reviews love them.
I wanted to hear from someone other than a youtube reviewer.
My room is maybe 16 ft square and is on the padded side for a living space.
I've noticed that the 300s are more sensitive to separation than other speakers. They sound better when they are placed further apart. When I moved each speaker from is original position another 2 feet outboard, 4 feet total additional separation, the sound quality improved. That puts them further apart than I'd place stereo speakers normally. That might just be my room, but I thought I'd mention it.
Makes sense. What is the total distance between them?
Right now, about 8 ft OC and I'm seated about 9 to 10 ft away.
That should be perfect 
I ended up selecting the 300s over the Fives for stereo for a number of reasons:
While listening to a wide range of sources, the difference between the Fives and 300s was minimal. The caveat being the 300s were paired with a Sub. I found that the Fives really didn't benefit from the Sub, and since I had the Sub anyway, it was natural to leave it paired with the 300s. I did tune both sets of speakers with Trueplay, and that did improve their sound.
I liked the way the 300s filled the room with sound. They outperformed the Fives in the way they sounded clear regardless of your position in the room. While they had a sweet spot, they still sounded good outside of that sweet spot. This led to an effect I'd liken to a live performance while the Fives had more of a studio sound. Either way, both speakers sound good and the presentation amounts to personal preference.
Finally, the 300s looked better in my Livingroom. Appearance wise, the Fives really need to be against a wall because the backs, while not ugly, are not that great looking. The 300s, when mounted on the Sonos stands, look good from any angle. Their power cord hugs the back of the speaker and disappears into the stand. I have them placed closer to the center of a larger room, so their backs are plainly visible.
If only they had a balance control. 
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