I picked up my first DSLR in 2007 with the 40D. I've since switched to the 5D Mark II and have gone through quite a few lenses: 17-85, 50 f1.8, Sigma 50 1.4, Sigma 30 1.4, 17-55 f2.8, Canon 35 f1.4, Canon 70-200 F4, Canon 70-200 f4 IS, Canon 17-40, and Canon 85 f1.8. So needless to say, I definitely have a good understanding of what I want in a camera set up. Over the past two years or so, I've consistently left my 5DII at home because it was too big/bulky to be carting around with a 2-3 y/o. Most recently on a 10 day vacation, I took the camera with me on 2 occasions - not what I'd expect from $3K+ in camera gear. I started looking at mirrorless cameras with the expectation of getting a Sony Nex when I learned about the E-M1. Today, I bought the E-M1 and 12-40. I have been a big fan of primes for a while, but with a fast moving 3 year old, I know primes definitely have disadvantages when compared to primes. I'm looking for two pieces of advice/input in this, my first post: 1. I am a big fan of the 35mm focal length. Is the Olympus 17 f1.8 the best offering at that focal length? I'd like a prime to cover off low light situation AND have a small lens when I want to reduce form factor even further. 2. PLEASE give me some assurance I'm not going to drastically regret the drop from full frame image resolution. Thanks all!