I learnt on the HR200!
The R2112 desingation I believe is political. Chris Heintz the designer left. HR meaning Heintz Robin. No longer wanting to be associated with Chris, Robin dropped the "H". But I learnt on a 2000 machine, still a HR200 desingation and CH left in '72?
The R2160i has an injected 160hp engine (vs 120hp carb) so is cleared for aeros.