mcintosh ma 6600 vs rega osiris vs nad m2

i want to buy one of this 3 amplifier, i have canton speaker who sound bright whit a deep bass. I like dynamic sound whit a good punch in the bass. Does anyone can advise me for the best choice?
Have not had chance to audition the NAD or Rega. Own the MA 6600 and simply love it. Good hunting, and post your final choice.
The ma6600 is way better. Audiophile flag-wavers will always slam mcintosh equipment for no good reason. The new range of integrateds they offer are very respectable. I have audiotioned the ma6600 and the m2. The mcintosh is much better.
I could listen to my 6600 24/7. You just never get tired of it! I've heard the Rega and while it's a very respectable amp, there's no comparison to the 6600 (YMMV).
Love my 6600! All of the above is true.
How would you go about comparing the NAD M2 with the McIntosh? Just curious. They are totally different pieces. The Mc is an integrated amp that does not accept AES/EBU or any other digital input and the NAD M2 does accept AES/EBU.

The NAD M2 is not an integrated amp. Its a direct digital amplifier.

If you actually compared them, you would need to say what kind of DAC you used with the Mc.

I love the M2. Coupled with the right media server, the sound is incredible.
I own the Osiris and it is fantastic. Compared it to the Pass Labs INT-150, Plinius 8200 MKII, Coda CSi, and NAD. To my ears the Rega is the most musical and refined. It has more soul and smoothness than the rest. Not to say the others are not good but the Rega is special.
I have just received the combo Isis + Osiris. Even being on burn-in process, I can confirm that it is just an amazing amplifier. I have already heard the Mcintosh and Nad and, for me, the Osiris is in another league. My previously set was a Gryphon Callisto 2200 Integrated amplifier and Gryphon CDP1. I had the chance of comparing the Osiris to Gryphon Callisto 2200 ( for me still one of the best integrated ever ) and I can assure that the Osiris is at least on the same level ( the Callisto has a bass extension and speed difficult to be match )but the Osiris has a "magical" sound..should be heard. It has an enormous sound stage and very transparent ...very, very smooth sound. Long listening session without fatiguing.. I am very happy with my purchase.
I have Rega Isis and Osiris on demo at home now and to me it is an excellent sounding system.More than enough power,huge sound-stage,non fatiguing with silky midrange.Guitars and vocals never sounded better.I have to mention that part of this great sound is ISIS which could be one of the best CD players around.The sound is liquid and very involving bordering on analog.I also have listened to Mcintosh 6600,it has many nice features, but it was a little underpowered and slower with less resolution, but still a nice sounding with good sound-stage.
Actually, the Osiris was the big surprise for me in this combination. I was expecting that the Isis would be great ( and it is fantastic ), however, I was not prepared by how excelente the Osiris is. For me, it is one of new references in the market concerning integrated amplifier.
I am testing the Osiris and Isis with the original Power Cable and the XLR connector from Rega. I am comparing them with Shunyata Anaconda and Furutech Reference III Power Cords and XLR VDH MC Gold. Sometimes, I feel that the more expensive cable set ( shunyata, fututech, VDH ) has more bass extension and body...but lacks the magic and transparency of the Rega´s cables..frankly speaking, I am in doubt about what better combination is...any experience ? Who has tested this Rega´s Combo used which cables ?