I could see the time saving benefits if you have a filter on top of the engine but that is all. I have a lift and during the time the vehicle is up in the air I do a thorough inspection of the brakes,suspension,steering,exhaust, CV/U joints. Check for leaks and generally look for anything out of the ordinary. Of course you can also do the other under the car fluid services as required. So I guess the question is, do folks that use extractors forego the other maintenance that requires being under the car. I see many flush the transmission without changing the filter, why bother? I guess it isn't too surprising on a board that the majority is fixated on the lowest cost /longest OCI available for their vehicle. Do oil extractor folks do the required inspections that require being under the car or do they skip them?