I have had my M80's and VP180 for about 9 months now and have enjoyed them from day one .
Recently i purchased an Amthem MRX500 and now the 80's sound even better .
Nice to hear that the anthem has made an improvement on the M80s. I am currently looking into Anthem's MRX line and leaning towards the 300. It has the feautures I want and the price I am willing to pay. I hear a lot of great things about ARC.
Some people i know on another forum have purchased the 300 and love it , esp for under a grand .
Arc is amazing and also can be bad because it can show faults with your room .