Originally Posted by
VPescado
Theoretically, Nexus might be harder to get as it requires the Canadians to clear you as well as the US, but I doubt that as a practical matter many folks are turned down by Canada while approved by the US.
You never know. As previously reported here, a single prior arrest for something like DUI (even from decades before) could make any foreigner inadmissible to Canada. Not sure if the USA applies the same standard.