Inspired by discussions here as well as in other forums, I am thinking
of trying out second-hand Quad ESL-63's. Would appreciate a few
clarifications:

1. What is the difference between "USA Monitor" and regular ESL-63
versions? Is the difference a big deal, in performance or price?

2. What is a good price for either in the second-hand market? (I am in
the US.)

3. I have an Audiolab 8000S. Will it be ok for the Quads or will I have
to buy a new amp?

Many thanks.