The extended cut is a few minutes longer, though most of the added scenes are throwaway bits. The hot tub scene at the motel is much longer, and unlike the theatrical cut where they seem oblivious to the nature of the motel, they are fully aware in the extended cut and Lloyd makes a lot of sexual comments towards Harry. Lloyd's bathroom encounter with Seabass is also longer, giving Seabass a few extra lines, indicating that he definitely wrote the note on the wall. Harry also taunts Lloyd more about his encounter while driving away afterward. We also see a close-up of Seabass's tobacco spit at the restaurant, Petie's death in the beginning is a few seconds longer, and there is an extra scene with Lloyd and Harry talking about Mary, before Harry's date with her.

The funniest extended cut scene involves Harry, while trying to fix the broken toilet, dumping his feces out of the bathroom window.

The theatrical cut has a much better pace and is a better movie, even though it is only a few minutes shorter than the extended cut. Though it's not on blu-ray, the theatrical cut is available in HD on Amazon Instant and I saw it on Netflix a couple of years ago.