The three mono amp sets I have tried that worked exceptionally with the MAXX 3's are the Luxman 800A bridged to mono,the ARC 210's and the Berning 200w Quadrature Z's --currently. I would also recommend trying the more powerful VTL amps based on my listening at shows.
As usual with poll's like this you will get polarizing opinions from people that do not mention context or specifics. I am sure the Isis are exceptional speakers, and if they are on your short list I would find a way to listen with them. They will likely be harder to find for demo than the MAXX 3's, which are at a number of dealers.