I'm not able to get out much too better understand differences between very nice and really nice Mono block amplifiers
Understand? How are you are trying to understand? I would suggest try and listen instead. Compare and contrast, ideally with same speakers on the same room. Any dealer should be able to accommodate this. They likely have available both for sale.
Now, if your budget is $5,000, and totally nothing wrong with that, no need to sweat the $25,000 amp. Buy the $5,000 amp that sounds best to you. Forget the $25,000 amp.