If I intended to do oil changes regularly this way, I'd get the type that comes with a 12V DC pump mounted to the top of a 5 gallon bucket. They are sold at marine supply shops for about $150. It has clip leads that you attach to the battery. I've used this type as well as the Topsider and IMO, it's well worth the extra money for the simplicity and convenience.
The Topsider U pump type has a warning printed right on the top that says not to use your foot to steady it while pumping, which of course is the natural thing to do. Reason is, the can is so flimsy that if you press on it while under vacuum, it will collapse. Been there, done that!