I've A/B/C'd the Behringers, Mackies and KRK V8s....
V8s hands-down for my tastes - tight low-end, excellent mids, and detailed highs. I liked them so much, I finally bit the bullet and decided to upgrade.
I got them in yesterday and installed them last night -- what a dream to work with -- they easily showed fine details on mixes I was previously happy with (and now feel like I have to re-do!)
They instantly gave me the impression that I would have been able to "hone in" more precisely on the sound I was after compared to what I heard from other monitors.
If you can afford the price tag, I'd recommend them in a heartbeat.
The Mackies were closer to the V8s than the Behringers are to either, but the Mackies were too smooth in the mids/upper mids for my taste.
The Behringers, although reasonable, had this flabby bottom end and smooth but muddy mids. The high end was allright but tended towards being shrill as opposed to "detailed."
Yeah, the Behringers are cheap, and given enough effort - one could get used to them, but there are so many better monitors out there, they're not worth the effort.
Bruce