Honda recommends 10w30 conventional for life. No reason it wouldn't work. My s2k had a rebuild about 30k miles ago. Bummer for me is the RMS started to leak after sitting for a year or so. Not bad enough to tear into it but it is annoying. I always wanted a Spoon engine, just to say I have it.
There's an old motorcycle video where engine builder always breaks in the engine on the dyno. His theory if you run a new engine slow the rings act like a course file run them up to high RPM the rings act like a fine file. This is how they break in racing engines straight to the engine dyno