Do Mono Block amps provide better sound ??

One of the the biggest advantages of mono amps is that you can run longer interconnects and the shortest possible speaker cables, where the signal loss is significantly higher. It is simple physics.

In a word, yes

it is like Spencer wrote. Depends on quality of course, but when you try same as mono you will hear the difference. Even with high sensitive Horn Speakers it is a better result (from my experience).

I have always found that a better quality stereo amp is better than 2 average mono amps. When you have superb amp, then mono amps provide just a bit more...this should be the last thing to do...after getting a top of the line Aye, AudioResearch, etc.

I've demoed several same brand stereo /mono amps and have heard no sonic advantage either way . The stereo amps were considerably cheaper so the choice was easy .

I have owned many different high end stereo amps and monoblocks. They have all sounded good to me, but you have to remember each amp has it's own sound. If the monoblocks sound better in your system, and you prefer the set up (length of speaker cables and interconnects, set up off your main rack) and price increase then go for it. I don't think you can go wrong with a good monoblock or stereo amp.