I should clairify, I don't think it's the Avon tire itself...tread pattern. it's the fact that the 240 I find will hydro a lot easier than a slightly narrower tire. Personally I found the 240 stock Metz did better in the rain than the Avon. I love the Avon in dry conditions, sticks like glue.
I'm sure you will have a different experience with the Avon on the R3T. It would be interesting to hear your thoughts when you ride on them in the rain.