It sounds “harder” and dryer. Musical instruments sound very good. I think for classical, I likely prefer SS. However, for vocal, it is not as sweet, and the sound is less holographic.The classic solid state complaint.
Pass Labs makes sweeter sounding amps, but not in your price range I suspect, since you also need some power. I would look into rolling tubes with the Mac and possibly placing it on a platform or other anti-vibration devices to help it out. I would also look at speaker cables, which are ***critical*** when using tube amps on difficult loads- the shorter, the better!