I've been using the Topsider (blue can, labeled as the Big Boy Topsider) for two years and six oil changes. No problems, as long as you get the rubber gaskets in place.
Pros:
1) It takes about 10-15 minutes for the oil to drain, but you can use that to replace the filter, check other fluids and the battery, etc.
2) It cost $50.00 in 2004, but as of now it's cost me $8.33 per oil change. I'd spend more than that in labor if I went to a shop.
3) You don't have to jack up the car or put it on ramps, and you don't have to unfasten a splash or belly pan, which so many cars nowadays seem to have.
4) The drained oil is already in a sturdy metal can. Seal it up, take it to the recycling center, and dump the oil. All done. No worry about a plastic drain pan leaking, as my last one did, or about pouring hot black oil into other containers.
5) If you overfill the crankcase or other reservoir, you can easily suck some of the fluid out without dealing with a pouring stream of oil.
Agreed, you need to be sure your car is designed to have the oil extracted via the dipstick. The dealer should know; if it's possible, they'll do it that way, since it's cheaper and faster for them.
-- Paul W.