But placing a cheap lens on a DSLR is basically crippling it. You might get some low-light advantages and a bit faster focus speed - but the entire purpose of a DSLR is to let you use the best lens for the situation. I read the review when it originally came out, and, while impressed with the hard work they put into it - It just felt like so much of an apples vs oranges comparison that I didn't get what they were trying to do.

One might claim that a $1,700 lens is a cheap lens. A fast prime for wildlife would be something along the lines of a 600mm f2.8. That's a $12,000 Canon lens.