I'm an amateur. I have a Canon 40D with a 50mm 1.8 that I love. I have four little boys and they are my main photography subjects. I'm new to the micro 4/3 bit and have the OMD EM5 and have been loving it for the few short weeks that I've had it. My only complaint is that the kit lens isn't capturing nearly as many good shots of my boys as the 50 does on the Canon. I'm saving up for a prime. What is the best prime for the EM5 for shooting kids - a lot of the time, indoors? I've looked at the Panasonic 20 but don't like the slow autofocus issue. The 25 is much too expensive. I've also looked at the Oly 17 1.8. It's more than I want to pay, but looks like the best bet. ??? I recently started reading up on the new Sigma art lenses - specifically the 19mm 2.5. Not sure how I feel about the f2.5. Anyone have this? Clearly I need a fast lens. Suggestions?