I bought a '94 ZJ a year ago. It had been used for towing. The only thing that was wrong was the remote access controls had crapped out. Dealer replaced them for free.
Haven't had a single claim on the extended warranty - probably wasted my money this time, but an extended waranty paid for itself the first month I owned my previous vehicle - after that it was sheer profit. I was concerned about the reliability ratings also when I bought mine. Maybe its a crap shoot - win some lose some, but mine has been a gem.
Jim Hodges (automotively challenged)
94 ZJ (4.0 L), 3" lift + 2" front spacers, ARB bull bar, Warn winch, ARB lockers, ZJilla rear bumper & t-case skid, ORGS super-nerfs, Rocky Road diff guards, JKS quick discos, BFG 31X10.5 AT KO, Borla cat-back exhaust, DirectHit ignition upgrade, Pro Power 175 amp alternator, Garvin wilderness rack, Lightforce driving/off-road lights, Alpine CD changer, Colormap GPS, 2 dogs