I'm not sure if climate matters all that much in making a 2-stage vs. 1-stage decision, but whatever you do be sure that the system is properly size so that the HIGH stage matches your heating requirements and not the low stage.
Here in the South, furnaces are routinely oversized -- sometimes 2-3 times what is actually needed. If you do this with a 2 stage furnace, then it will never run on high except when recovering from a setback, and you will basically have bought an expensive single stage furnace matching the output of the low stage.
Someone sold me a 66K/44K furnace for a townhouse several years ago, and it runs 5-8 minutes on low maybe twice an hour when it's freezing outside. I get big temperature swings and cold spots. Needless to say, I wish I had done my homework first.