No, Matching RMS rating is the best thing to do. However getting a larger amp (500w RMS) gives you some head room.
From what I've read on here. One forum member was pumping 1000w RMS through his CVR.

Mono = one channel.
stereo = 2 channels.

If you read the spec of the amp it will clear it up. Some amps are marketed at 500w two channels. So you might think, is that 500w PER channel? or together?