I have a 1625A that had a problem with them, in my opinion,
see thread http://arboristsite.com/showthread.php?t=17369
Some folks still swear by them, but I guess I am in that 5% that is not sure.
Do not know about the RG 50 but our Carlton 4400-4 has the greenteeth.
We have been told by the service department they are very hard on the drive train especially when they get a little dull. The larger surface area of the tooth creates more wear and vibration on the rest of the machine.
If we had to over again we would not use the greenteeth for this reason.
Eventually the manufacturer should become aware of this situation.
