i've had a letus35 mini for a while now and i love it! it flips the image for you already too, so that's nice.
btw, they want you to use prime lenses because with a zoom lens you lose more light, and also, prime lenses are a lot more crisp and clear.
you lose some light just by having a 35mm adaptor on your camera, then you lose a little with a lens. a good prime (50mm) you'll only lose about 1.4 or 1.8 f stops. if you have a zoom lens you're losing about 3 f stops or more
