I don't have direct experience with Paradigm, but I did try mis-matching speaker designs in my HT. I had an ML Logos center with AP Virgo mains. As Sdcampbell stated, I found that perceived speed was a primary determining factor of compatibility. Tonality was less of an issue when considering the nature of the home theater experience. Multi-channel music has demands that requires separate examination.
I believe it is a fact that matched fronts will provide optimum results for most applications. In my case for HT, the Virgos allowed a broader more even coverage than ML Aerius Is in the mains position. If you listen hard enough you will find distracting elements to the sound. If you are watching and listening to enjoy a video, it won't matter. I found the ability of the center channel speaker to resolve as necessary was critical. I felt the ML center clarity was excellent and the AP holographic abilities made for a nice match.
I believe it is a fact that matched fronts will provide optimum results for most applications. In my case for HT, the Virgos allowed a broader more even coverage than ML Aerius Is in the mains position. If you listen hard enough you will find distracting elements to the sound. If you are watching and listening to enjoy a video, it won't matter. I found the ability of the center channel speaker to resolve as necessary was critical. I felt the ML center clarity was excellent and the AP holographic abilities made for a nice match.