rushwj,
I would of course recommend the 990 as it does very well with music and I am perfectly happy with its performance. As I am not totally biased, you may want to listen to the Arcam though, as it is supposed to be even better with music; I just didn't think it would be twice-the-price good, so I went ahead with the 990 and haven't been sorry.
The 755 amps I use are incredible. I don't think you can go wrong with the performance you get at the price. I would expect the new amps coming soon to be of equal value and performance.