I will start off by mentioning I am planning to get Fuji x100s and I'm rather very confident with this decision. I tend to do quite a bit of street photo and photography which requires people to stay natural thus the need for discrete small and quiet camera which I understand x100s is. My Nikon D300 is not exactly the perfect tool for this type of work and as I was thinking about I realized that replacing Nikon with XE-1 would also be some kind of solution. While I understand the advantages of Fuji system I also realize there are few shortcomings comparing to traditional DSLR system which Nikon is. So here is the thing - I do shoot some sport once in a while. Nothing too extreme, mostly Brazilian jiu jitsu tournaments. While in terms of ISO Fuji would greatly outperform my older D300 I am wondering whenever AF would be acceptable. I would like anyone who has a hands on experience with both Fuji and DSLR system to advise whenever using the first one has truly some major disadvantages as for example in sports. Can we even expect Fuji system to be able to replace DSLR systems in this kind of field in the future?