Hello there,
Actually though when you compare NiMH charging to Li-ion it become apparent that the charge algorithm and/or circuit is simpler for Li-ion than for NiMH. NiMH is harder to charge basically, required careful incremental measurements. For Li-ion only the voltage measurement has to be accurate, and not even that if we allow for a decent margin of error.
Compare the two charging methods and see what you find out.
I've been doing this for almost 10 years now without a single problem so i tend to recommend Li-ion cell, at least when charged one at a time.
I never recommend charging in series or parallel however, but lots of people do this too.