Had a recent bad experience w/ Jiffy Lube as well- they changed the oil on my 01 OB wagon just fine, but re-used the "crunch bolt" (?) they pulled out of the car to drain the oil, so the seal was not good. Resulting in leaks, stained driveway, bad smells, angry wife, general distress. Not good, not fun.
Finally brought it to the dealer, they fixed it by changing the oil.
Could be a source of the mysterious burning oil smell I've seen discussed in the past.