While I too do not use a radar detector in Ontario, I do have one for when I go down to the US. It is the Valentine One.
There really is no better detector on the market.
While in the comparison tests there are now detectors that score as well or better in some categories, overall the V1 has been the safest bet for ages.
The big advantage with the V1, other than the range, is the display that tells you where the threat is coming from. This is a huge advantage is you can determine which threats are worth worrying about. Also, the unit is always upgradeable. You can always send it in, and for a small fee (relative to the cost of a new unit) have them upgrade yours, or send you a new one.
The problem with this is purchasing one in Ontario. They will only ship to the US or provinces that allow speed detecting devices. http://www.valentine1.com/