We no longer list our amp power ratings by RMS as these tend to not give true results as tests are always done using signal generators and specific waveforms which don't reflect in comparison to music, music comes at fuller frequencies and non linear dynamics which of course as I'm sure you're aware is nothing like a test tone generated from a signal generator. There are lots of topics on the internet about this should you wish to look into it more.

Please also refer to the following article on this topic;

As a rule of thumb, you can assume RMS is around half the peak value