I have the modified AK100, the RWAK100. I have to say that the RWAK has very clear and neutral sound, with plenty of detail and great form factor.
Between that and the R10, I wouldn't be able to part with either.
The R10 has a different sound signature with a fuller sound, and more power. It sounds the best of any portable player that I have heard.
When I need portability I use the RWAK, but sitting at my desk at work, or lying in bed listening to music, the R10 is what I use.
The point is, there is always room for more than one player.