FINALLY a Mani-2 poster!!
OK- I have owned them for years- in fact I now use 5 of them in the home theater system. Current amp is Theta Dreadnaught- excellent match. The Dread does 400wpc in to the Mani's 4 ohm load, and uses a massive 2.2kVa transformer- sound is very natural for SS amp.
I have also experimented with vertically bi-amping the Mani's as well, with good results (using a preamp with 2 sets of balanced outs for main channels). The difference with the bi-amp was not 'night and day', as Mani's are only a 2-way design, however bypassing parts of the crossover can't hurt, and I found more (slightly) more resolution; energy; and purity with the bi-amp.
Other than the Theta, another top recommendation would be Sim Audio- W5 (2-ch), or new Titan (up to 7 ch). HIgh damping factor; wonderful stability in to low impedances; and an ability to take control of a woofer are the strong suits- in fact, I may have gone the Titan route, but bought the Dread just before Titan was launched- absolutely no regrets though- I found Dreadnaught more musical, Sim (slightly) more accurate but with more slam- depends on what your application is.
Lastly, with Mani-2's, don't skimp on cabling. I went from a half-decent Audioquest spkr cable to Cardas Golden series, and it was night and day- much more fullness to the sound- especially noticeable on center-channel. Mani's need spkr cables that can carry lots of current effectively- same with interconnects. Good luck in the quest.