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!

I'm looking at gettting a pump for my car, and came across some forums which
insisted that topside pumps don't get the sludge out of the sump as well as a
proper oil change.  This was the most recent forum I found with information
on the subject though, and the only one that recommended these devices as a
regular alternative to a traditional oil change.

Despite the comments I've found, I'm tempted to buy a pump.  I'd make sure to
do an ail flush every time I change, to get as much of the sludge out as
possible.  The other option of course, is to alternate self-change and
professional change (I live in an apartment, and don't have anywhere to put
my car on jackstands to change the oil from underneath myself), maybe with a
2:1 or 3:1 ratio.  Am I nuts?