Slightly cooler smoke, but more potential for condensation buildup. Also, lighting the pipe can be easier (it's easier to focus on something a foot or so away, opposed to right under your nose), depending on the shape. And, if you hold onto your pipe while smoking, you don't need to bring your hand up to your mouth to take a puff.
I think I have a Cobbit Dwarf. I have one. I also have some other briar churchwardens. They're all nice. Cobbits are less money so if you don't know if you want a churchwarden it's a cheaper way to try .
I have a cobbit wizard. I like it, as I do all my corn cob pipes. The stem it comes with also fits most of my other cons, so I can adjust size as needed. I find churchwardens to simply be a different way to enjoy a pipe. It looks and feels cool...I wouldn't say they smoke any better or worse though. If you dig the style, go for a cobbit. Great price for a great pipe.