Yes I have heard of them and own two such units. I have the Rotel RHB-10 (200-watt version) that sold for $3500 new (picked it up back in 97 at close-out at PX when I was in Germany for $500). I also have the pre-amp RHA-10 that sold for $2500 new (also picked up at close-out sale for $350). How do they sound? Exceptional. The folks at Rotel turned their engineers loose for both of these models without any price constraints. Amp weighs 60 pounds and is a true dual-mono product with the highest quality materials/components. Both models are beautiful to look at. If you ask the folks at Rotel...they will tell you they have yet to make anything (amp/pre-amp) that sounds as good as these units even 7 years later. Interestingly enough, units did not sell that well despite outstanding reviews in Brit press. Don't even think you could get them in the States although configured for 110 or 220 watts. Guess no one wanted to spend that much on Rotel products.
