I don't have any experience with either amp, but there are some specs missing from the site that could have some relevance.

Intermodulation Distortion is listed for the 7500 but not the 2200. Also damping factor is not included. Slew rate is not reported for the 2200 (although most modern amps are fine in this regard).

Also, while many people don't believe anything that is different about about 20Khz makes a difference, there is plenty of evidence that a component, or design, that has issues in the ultrasonics can manifest issues within the audible domain, even though they are extremely difficult, or in some cases impossible, to measure in the audible range.