Bottom line, as in all these type matters, to get a written answer from FCL at the CAA, as they will ultimately determine the validity of claimed experience for the puposes of licencing.
I would say there are plenty of anomolies stroke loop holes at the moment. However, comma, I would suggest cease thinking in terms of R22 or AS355 types for 2nd pilot time. It isn't worth it, and will not help one iota with future employment; appart from displaying iniative (doesn't help with insurance requirements though).
One assumes you are talking UK/JAR requirements.
You must talk to the sort of operators that use these types though to get real, down to earth answers. Phone Burman or PDG or PAS or Lynton, to see what they have to say about it all.
I hope they conccur, but wish you all the best.
------------------
Another day in paradise