I'm getting super attached to my NEX F3, but what I don't like about it is that unlike a traditional SLR, there's no mirror that blocks the sensor. Should that bother me? I never had a problem changing my lens in the open with my Canon DSLR, but I feel that if I go out with the lens that's attached, it has to stay on or else dust will flood the sensor. Should I be worried especially with the fact that I use legacy lenses? I have some Copper Hill solution that I used to clean my DSLR sensor, can I use that to clean the NEX sensor since they're the same size?