Hi Mike,
Might be an unfair question, but what did you in particular prefer about your system vs the Quads? I can imagine a legitimate answer would be 'everything' given your system...but in my case, i nearly bought the Quads and did a shoot out with SF Guarneri, small and big Quad ESLs, the SF Amati, SF Strad and Maxx II.
I was very suprised at how much the SF Guarneri and smaller Quad sounded very very very alike. And it was mainly on the element of WEIGHT and SCALE where the Maxx II and Strad really pulled away from the fantastic Quads, although i also recognize in the case of the Strad, you really had to have remarkably powerful current to ensure you max'd out their speed, alacrity to try to keep pace with the inherently faster Quad.
So for me, it is weight/scale-power where I felt i needed something else...otherwise, i find the Quad a beguiling speaker with an amazing combination of alacrity, detail, nuance...and yet tonal purity with almost no sense of artifice.