Mono Blocks / why are they not more prevalent? + Wyrded4Sound SX1000R

They aren't used more because they don't provide said benefits. Simple as that. Enjoy your cheap AVR amps that sound the same.

I try not to spend money on stereo unless I begin to hear a "lack." Something begins to bug me. I don't know how I know, and it might take years of listening to a piece of equipment to realize I need to replace it.

I have a 25 year old Hovland Radia which sounds great driving my Sonus Faber Olympica Nova speakers. I hear nothing the Hovland does not do well. You might say I don't have very good ears, but they're my ears which have chosen my stereo.

Mono amps are on the bottom of my list. BTW, I live with a wife, and big booming bass is the last thing I need. I guess if somebody wanted a macho stereo he would buy big Boulder monos. I'm more interested in delicacy and layering, and I can't imagine monos improving on what I have. I do have a few things on my list of things I want but don't need. A really expensive phono cartridge and streamer would top the list. Mono amps wouldn't be on it, though.

If you are happy with your set up, whatever it is, that is the best one.  For you.  I have participated in double blind fold tests with "golden ear" types, who were convinced that their _____ fill in the blank sounded the best.  When it comes to mono blocks vs. otherwise equivalent stereo amps from the same maker, I have yet to witness even one of these tests where the outcome was clear.  In other words the participants were guessing.  Every time.  This phenomenon has played out in my personal experience at least 6 times over the course of many years.  These were carefully controlled tests, with careful sound level matching by credible people.  You can take it from me, the differences are either non-existent or so miniscule as to be not worth worrying about.  Suit your ego, but don't fool yourself.

I own SX-1000R's driving Yamaha NS-5000's. Monoblocks shed heat more efficiently. They make it easier to package your system efficiently. Get a nicer power strip. 

The true value of mono blocks are realized when the speakers demand the dedicated power supplies and output stages in two separate chassis. This is true when speakers are particularly low efficiency. 
fir high efficiency speakers the value diminishes and it becomes less of a priority.

Typically, the monoblocks handle transient loads a lot better when the speakers demand it. The drum attack becomes immediate, the bass sounds tighter and generally “speed” of the speaker response increases.

thus improvement is less audible on efficient speakers as you hardly find yourself lacking output.

my 2 cents.

MO