I ran the original Quatro's for 7 years and loved them. They absolutely reward you for very careful work on speaker placement, and tomic601's list of needed tools above is spot on. I can testify to the 1/4" claims.
One thing that amazed me was the importance of getting the correct tilt angle to hit you correctly at your listening position. Richard Vandersteen underscored that to me on the phone, and when I dialed it in, "Shazzam!", there was that beautiful midrange singing clearly! And don't try filling in dips in bass response too much - - I believe the manual emphasizes that, too, but I lived it. It can suck the life out of things. The 11 band bass equalizer is best suited to tame peaks.
Enjoy 'em! I would have loved to have played with the CT versions!