I just answered a question on Quora that I thought would be fun to repost here.
This was the question: Has Anyone switched from a Full Frame DSLR Camera to an Micro 4/3 Camera Exclusively? And if so What have been your results? - The 2 cameras I am comparing is the Canon 5dMk3 and the Lumix Gh4 - I am a Fine Art Photographer and I shoot Events as well. (No Sports or Wildlife though)
This was my answer:
Yes, and I regret it, a bit - see below. But your milage may vary depending on needs...
I swapped my Canon 5D mk2 and L lenses for an OMD EM5 and a selection of lenses when it came out. Long story short, I lost money changing systems and have since lost even more rebuilding my Canon system! But the thing is I really wanted and needed a change, a fresh start and changing systems did that. I literally went through a ton of different camera systems in the 3 years since that change and have actually enjoyed the whole journey. I've even had times when I only had film cameras and made money with them. The (whole) road looked something like this:
But you know the thing that I realised somewhere along the way? The camera didn't matter. Now I know this gets thrown around a lot but it is quite something to realise it. I looked back at my work and realised that my images had a look, a style and that no matter what system I was using, digital, film whatever, I was producing work that clients were paying for and I was happy to deliver.
The many changes did help me realise what elements are important to my work - control over depth-of-field, haptics, ergonomics, emotion in the tools - and this has given me a better understanding of the work I do.
So go ahead, but be warned: it may be the start of a fun, expensive and rewarding journey, where you try to end up back where you started. A little poorer, but also a little wiser.