Usher S520 versus PSB Alpha B1
Let me weigh in with my view on the comparison we did. Like the vortex said, the comparison was way too short to make conclusive observations, so these are very very preliminary observations.
The PSB and the Ushers seemed to be reasonably close overall (which makes the PSBs excellent value for 14k), but I decidedly prefer the Ushers for the following reasons (again i am an Usher owner, so ownership bias must be considered by people reading this):
(a) it had decidedly better dynamic range (which is one of its strong suits), the sound had more air about it, especially on the 'morph the cat' track from the album of the same name by donald fagen
(b) i liked the sounds of how it reproduced the mids and mid-bass, guitars and cello and so on...basically i preferred its tone/timbre
(c) it seemed to have tighter bass, but the PSBs were rear ported and there was not enough space behind them to give them a fair run.
(d) the PSBs seemed warmer, but thevortex and I disagreed on that
Where the PSBs and the Usher were close, was treble detail and extension, LFE, and the broadly neutral presentation. There's more in common between the PSBs and the Ushers than say the Epos ELS8 or the Wharfedale Diamond. The Epos has better LFE and warmer mids, but loses out in detail and high frequency extension. The Wharfedale also has better LFE (perhaps even more than the Epos), but it's tubby and more 'mass market', not lean and tight and 'hi fi', sweet (artificially?) mids, and less detail.
Comparing the Usher to the BR2, the BR2 again had better LFE, but falls slightly short in detail and well short in dynamic range. Great speakers again, and if you want to cover a bit more of the frequency spectrum than the Ushers or the PSBs, this would be a good choice. The Ushers and the PSBs in the long term would probably need to be augmented by a sub to reach below 50 hz, whereas you could live with the BR2 alone for a longer time.
The comparison was too short to make any conclusive observations though. I'd love to do a more detailed and painstaking comparison (with an SPL meter and test tones and the works) of all these speakers if i got the chance