It all comes down to price.
The 265WT lists for $299.99 and has the free NAVTEQ service. Not all the features are available for Toronto, but you should be OK traveling in the U.S.
The 785T lists for $599.99 and offers the optional MSN Direct service, which is free for the first few months and then costs $50 per year.
While MSN Direct has more bells and whistles, both of the services provide the same traffic information.
Now most of the cars have the GPS built-in, if you need to upgrade the map, you can go tonavteq map update
update it, you may also find a Navteq coupon there.