Thanks for the heads up. I take it that it comes with different sizes of pipes
I used to think this but as long as it is done after a run no issues. In many cases the extractors will actually get more oil out than removing the sump plug. The sump plugs aren't always in the bottom of the pan and due to the fact there is a difference in thickness in the flange and the sump there is often a small lip of a few mm.(I aprreciate there cases where that may not be the case)
When you have a extractor you are far more likely to change your oil often than if you don't so the likelihood of there being crap left in the sump is far less anyway. When I first got mine I did a test, sucked it out with the extractor and then removed the sump plug and not even a drip came out. Due to the shape of different sumps there is a bit of practice required in getting everything out.
IMHO it's worth getting a decent one, MityVac(Also rebranded by SnapOn) or Pela seem to be the best.The performance on my MityVac is way better than my previous one.