I just got a 5D. Turns out it has the buggy 2.0.3 firmware already on it. I shoot in 30P so I'm thinking that I'd just like to try Magic Lantern but I know it needs 1.1.0. I've also not heard of a success 'downgrading' from 2.0.3 to 1.1.0, though I have heard a report that it doesn't work.

My question, before going through an hour or 2 of frustration is: If I try to install the 1.1.0 firmware over 2.0.3 will I be successful?

Thanks for any advice.

I know somebody at another forum whom I trust who claims to have downgraded from 2.0.4 to 1.1.0. I haven't done it myself though, but I haven't tried either.