What ho Squiffy!
I guess the R22 and the Bell 47 are a bit chalk and cheese as you say, but I think that the R22 had more relevance in teaching people to fly a modern helicopter, as it has a low inertia rotor in common with many of the helicopters now flying in Europe. Despite the teetering rotor (which is also the cause of some of its handling problems) the offset hinges also give it quite good control power (waits to be shot down by a real expert here!!)which is also similar to many of the modern helicopters students would hope to go on to fly.
It has to be said that the reason the school where I was working at the time changed was purely for reasons of cost, (the other types being considered being Schwiezer 300 and Enstrom F28) but the R22 appeared to offer considerable cost savings over anything else. Most of our students went straight from the R22 to the AS332L or S76.