Dante and Randal are perfectly contrasted men, each one being the perfect antithesis of the other. Dante's glass is obviously half empty, while Randal's is constantly being refilled. I love to see these two characters interact, no matter what they're talking about. Smith's short film, "The Flying Car", shown on The Tonight Show (a few years back) is a perfect example of the character's wonderful chemistry.
Also, the man who played the old Jewish man (Al Berkowitz) was by far my favorite actor. I wish I could see him in some other role.
Many have accused this film of being unnesessarily profane and disgusting, but I feel that intermittent f-bombs and terms like "jizz-mopper" are crucial elements of the character's identity, and quite frankly are words our society DOES use. Art imitates life, as they say.
This is Kevin Smith's funniest and finest story. The directing/photography leaves something to be desired, but as a green filmmaker myself, I appreciate Smith sticking his neck out and doing something like this. It gives me hope for my own films.