MaxL is right, there no longer is a "conversion cost". That was just a tactic to keep value in the Canadian market when the CDN dollar was on par last year. US cars have both metric and imperial speedometer so no need for the instrument panel swap.
Obviously some of these guys commenting in this thread WORK for dealers selling cars in Canada and are going to try convincing you to buy in Canada. There are significant savings buying in the USA.
True Canadian dealers will not honor the maintenance, but they will the warranty. So what, so you miss out on 2 free oil changes? Bring the car down to the US for inspection II.
Anyone that suggests a US car will be worthless in Canada when selling is just blowing smoke up your rear-end. ALL cars depreciate, it's not an investment! No doubt somebody will buy it, just as you did. You'll also be able to offer it lower as to paid less.
Read this current thread from another importer. http://www.e90post.com/forums/showthread.php?t=360292