Worst I know of is the old Lindberg - and it really ain't bad at all. And Wurger is dead on. With some work and creativity you could make it a real gem.
UPC had one in 1/50 and you can never be sure about those guys. Their 1/50 F-86D was way above anything else at the time but some of their 1/48 and 1/50 stuff were more along the lines of Aurora. Based on the attached picture it appears to be a copy of Lindberg's.
LOVE that Lindberg box art, though!
I have a Hobbyboss Me-262 but I have yet to open the box.