Hi,
You need to audition a number of amplifiers and determine what you prefer yourself. I've spent a lot of money in the last few years and had a few different amplifiers in my system.
The CI amps are smooth and mellow and do not have the icy steelness of, say, NuForce.
I've listened to the nuforce ref 9 v2 amps and they sound pretty good and certainly don't sound an 'icy steelness' sound. I personally don't have nuforce gear and I'm not defending them to you for this reason.
I bought an odyssey khartago and I was really disappointed with its sound as it wasn't transparent enough for my system. I've read rave reviews on this board about them, however, I personally didn't like its sound.
Currently I alternate between using a Spread Spectrum Technologies 'son of ampzilla' and a highly modified ps audio hca - 2. Both sound pretty good.
My opinion is decide on a list and audition these amps in your own system. You live in the States and should have no problem doing so.
Good luck.
Rod