I heard that the earlier series had a wide gear range. The newer Quetzals such as the Azteca are undistinguishable from the Evox. Some of the up-market Quetzals have better components and I believe that there is an aluminum model available. Had I known that at the time I bought mine, I would have spent the few extra bucks to get a lighter bike. However, all things considered, the bike is working out ok. There is a third name these bikes sell under. It is Mikado as in the G&S Operetta. My bike even says on one of the tubes "designed by Mikado."

Cheers

Charles