L322 or disco 3

Hi im looking at upgrading my trusty TD5 soon and i quite fancy a 03 or 53 plate L322 vogue , but have heard the auto box is not very reliable ? is this right or just hearsay ? i fancy an auto next as im getting lazy so i was wondering if the same gearbox is in the disco 3 auto? or is it a better box, I tow a 26 ft caravan that weighs almost 2 ton so i need the grunt/weight thing on my side any advise would be appreciated thanks