I've used this item to change my oil for years!
Great thing about using this is that since rotary engine has oil filter from the top, you don't EVER have to jack up your car to change oil!
All you have to do is insert one of 2 probe down the dip stick hole and SUCK IT UP! Ok.. That sounded kind of weird....
I could change my oil in 15 mins. Mostly just waiting for the pump to extract out the oil from the oil pan. Some say this will extract more oil than conventional draining.. I've measured before and its about the same.. If there is might be 1-2% DIFFERENCE!
I paid about $85 shipped from,
http://www.griotsgarage.com
Search for "Oil Extractor".
I ALSO use this to empty out coolant from radiator and I also have a brake extractor.. Which is pretty much the same as this unit.