Ground source heating is the same through out the country.
The pay back depending on the tax incentives and your local utility company incentives should be from 7 to 15 years.
You will also enjoy other options like drive way melt, in-floor heating, and pre heating your domestic hot water.
For more information:
Read "Is my home well-suited to geothermal?" a Q&A answered by Mick Dalrymple.