A canonical URL is essentially a "base" URL for a given listing created by Amazon when you create your listing.
Here is an example of a Canonical URL: http://www.amazon.com/NatureWise-Garcinia-Cambogia-Suppressant-Supplement/dp/B00B5H5BGA/
Sidewinder's ability to lock down a merchant Brand enables Blasts to spike ranking for any relevant keyword regardless of organic position.
You want to use SideWinder in the situation where you are at the bottom of rankings for any keyword. If you are closer, say within 20 pages of search for a keyword, You would want to use HeatSeeker.
Since HeatSeeker is our proprietary URL structures, we will not explain the intimate details of the systems we have built. However we can say it is not a Super URL, it does not use timestamps, and it does not even specifically target a listing's keywords. It is unique, automated, and incredibly powerful at ranking products on page one very quickly.
Want to run your own "custom" URL? Get in touch with us. We can input a custom URL for you once you have scheduled your promotion. Once we have tested it for accuracy we will input it to run with your promotion.