As a former Innersound Eros owner, I would have to say that the Innersound ESL300 amp will be one of the best "bang for your buck" amps you could find. As Bignerd recommended, I would also use a tube preamp. I would stay away from tube power amps. I'm not sure of the model of ML speakers you have (hybrid, full range), but if they are like the Eros, they will be a very difficult load for the majority of tube amps since the impdence drops to very low levels in the higher frequencies.
If you are on a budget, and don't like the Innersound amp, look for some of the older Thresholds (T400?) or Krells (KSA-KST100 or 200) out there with big power supplies capable of "doubling down" into at least 2 ohms impedence.
If you are not on a budget, you may want to consider bi-amping.
If you are on a budget, and don't like the Innersound amp, look for some of the older Thresholds (T400?) or Krells (KSA-KST100 or 200) out there with big power supplies capable of "doubling down" into at least 2 ohms impedence.
If you are not on a budget, you may want to consider bi-amping.