[simplechamp]

I looked around a bit online, and at the Wikipedia entries on CVDs and universal joints. The section about CVDs talks about what was used before CVDs were invented and it says: "similar four wheel drive vehicles used universal joints, where a cross-shaped metal pivot sits between two forked carriers. These are not CV joints as, except for specific configurations, they result in a variation of the transmitted speed."

I know Wikipedia is not the end all be all information source, but to me that seems to imply that although similar they are two different joint types. The universal joint does not transmit the rotation with a constant velocity. The article also mentions universal joints become more "notchy" and difficult to turn at more extreme angles, so that basically answered one of my questions. The universal joint is a more solid joint, but the CVD is easier to maintain and can handle the higher angles better.