You should audition a bunch of amps and go from there. I did this and found the Classe to be an excellent match for my Aerials. A word of caution: do not underpower your speakers -- the resulting sound will be horrible. I did this with a CA-100 on my Aerial 10Ts -- horrible sound. Now, the CA-200 is a different story -- the best amp. I have ever heard on my system. (vs. Krell, ARC, Sunfire, ATI, Bryston, etc.)
A CAV-150 will do 300x3 (bridged) quite well -- I use this for my center/surrounds with good results. You should be able to find it used for around $2800-$3k. Of course, realize this bridged config. isn't optimal.
--Mark