i think i use the two for different things. currently, i couldn't tell you exactly what the difference is, but i know there is one.

moving your archives would be a royal pain in the ass. i don't even know how you'd go about it.

setting up a blogger account to upload to your own domain is pretty easy, so on the technical side, that's not a problem.

major drawbacks: commenting is weird. no one can keep track of it but the blog owner, as the fishie says. also, no private/friendslocked posts.