Expectations after re cap of power-amp

The 2 ~~coffee can~~ sized caps, must be the M Supreme SGO caps,,,Yes?
I have a  apir of 10 UF sitting on my shelf waiting to go in a  new xover for my SEAS Thor speakers xovers...anyway,,,there is a  YTer,,~~AudioSurgery~~ who displays his work ina  series of vids, showing off his recapping on various amps, Uses M top line caps,,I can  actually hear the sonic improvements on his mods.
I have my Jadis Defy in the shop, for something stupid i did to the unit,,and will have the tech swap out some critcal caps for new M SGO caps,,,I can only say from my experience on my  cayin cd17 Mark 1 player, with 8 new M caps , noted a  nice gain in sonics, dynamics. Subtle, but notable. I expect more  Notable gains in the jadis recapping., vs the cd player recapping
https://www.youtube.com/watch?v=HGWcXN_zsR4

Yes agree, if the caps are laid out cleaning, its nota  difficult task for the DIYer,,,The Cayin CD17, was not simple, required the board to be dis assembled and soldered from bottom....,,so if the caps are laid out as ~~Scaffold~~~ design, anyone can make the mod, just clip the wires, solder on new caps, But if on a  tight preassembled baord, like jprrp1's Marantz mod , and my cayin 17 mod, these mods require a  tech who is WILLING to take it on. 
Some tech guys won't touch it, or will cost ya, My Cayin mod cost me $250 just labor. Worth it? I'd say yeah, Caps were like $300 and tech fee $250,,yeah, i now have greater dynsmics/sonics. 

Interesting post. Names of my components withheld due to persecution. I recently purchased new $8000.00 speakers. A well respected dealer in Milwaukee suggested that I replace my 20 plus year old Adcom GFA 555 II amp after heavy use powering my old Infinity Kappa 8's which are known as power hungry speakers. He mentioned for the money it would cost it would be better to buy something new. I'm all set with my system now but thinking of a 2nd system since I have an old not being used pre amp and CD player. Just bought a pair of speakers from a friend for $500.00, new they were $2000.00, handle 250 watts. Dealer said to run them with my Adcom until it fails. If it damages the speakers I'm not out much. What are your thoughts?  

Re-cap the Adcom for use in the second system?

Jon Soderberg of Vintage Amp Repair used to work for Threshold back in the day and still works on repairing and upgrading Threshold, Forte, and other brands of amps. He does excellent work. He replaced the power supply caps and the bias pots on my Forte amp. There was a substantial improvement overall. Here is what I want to tell you. Given the age of your Yamaha M-2 (nice amp by the way) you also want the tech to replace the bias pots with the newer superior enclosed bias pots. Better to do it now while you are replacing caps.