opinions on Rega RS1 speakers

You are right ..they are quite incredible.I've had some round here which I purchased on a/g recently for a friend on a limited budget. I normally listen on Lowther dx4 Medallion horns with various SE DH Triodes 45,300B,2a3,and was stunned, by their detail and overall blackness and sharp relief.I almost did not want to let them go.You're absolutely correct to say that they leave many other reputed brands in the dust.This uncanny ability,I think lies in the fact that smaller PAPER voice coils are more realistic than plastics,kevlars and the like.The trade off as with any thing in this game is whether you get sufficient bass for your taste.If you like acoustic and vocal music,you'll be ok.You can make up some ground(low frequency)with a closer listening position or in a smaller room & closer positioning to back wall..go for it...john