It's probably going to be a fantastic tool that will help get you amazing photographs. It is a good investment in technology, as there are improvements from the 5DMkII. That said, the 5DMkII is still a fantastic camera that produces amazing results as well. Personally, I would go with the 5DII and pick up an 'L' lens to go with it - you'll not be disappointed. I prefer the 70-200f2.8 which, if too costly, you might want to consider the 135mm f2.0 L - which is an excellent lens; or another prime lens like the 35mm L. Cheers.