I have auditioned the Monitor Audio S6's, NHT ST4's and the B&W 603's. I liked all of them. Does anybody have knowledge of all three that you might could share your opinions? If I hade an extra $2k I would probably get the ProAc Studio 140's, they were awesome.
They are all well made speakers from reputable companies and you will find positive reviews on all of them. It all comes down to personal taste and how they sound in your room, rather than how they sound at the dealers showroom.
I own Monitor Audio GR10's in my upstairs media room and they are excellent. I also own an old pair of ProAc Response 2's (rosewood)--and they are as awesome today as the day I bought them. But ProAc speakers are indeed expensive in whatever niche they compete. Smarter to buy a used pair at Audiogon and take advantage of the price reduction to reduce the fiscal pain.