Stereo or monoblocks

I have monoblocks though it’s due to sound performance per dollar. There are excellent stereo amps and crappy monoblocks. 
 

If you can audition - I recommend it. 

You can probably get a better stereo amp than monoblocks at the same price. If you compare monoblocks amps to a stereo  amp of the same design and watts per channel then monoblocks will have the better performance, but at a higher price tag.

Most important is the sound of the amplifier once integrated into your system. Pick the one that sounds better. Second, I prefer mono blocks because I believe they have the potential to sound better but more important you can use shorter speaker cables that can be expensive, so the savings there can be put toward the greater cost of the mono blocks.

Two amplifiers that I own (both excellent) are dual mono

EVS 1200 (TweakAudio)

Voyager GaN 350 LSA

Im pretty sure there are others

Especially if you have speakers of less than 8 Ohms, speaker cables can be critical- monoblocks allow the speaker cables to be shorter, thus reducing the artifact they might impose. If the monoblocks have balanced inputs, this can allow the interconnect cables to have no 'sound' of their own as well.

The power supplies of the amps are obviously not shared so the power for the amp will be cleaner. This can allow the amplifier lower IMD which is audible. Because there can be less current limitation to the power supply bass impact can be improved.