For those who are saying only a fool would buy this lens...I bet if it were a Canon-built lens, there would be several who would be pouncing on the "fool" name-calling.
If it were a Canon lens, it would have autofocus (unless it's a TS), so pouncing on them would be warranted.
I honestly can't imagine how anyone puts up with a manual focus lens. Manual focus lenses are fairly specialized pieces of hardware, usable only under fairly controlled environments—studio photography, still life photography, possibly landscapes (but only if you're not in a tour group that must adhere to a schedule), etc. I own a couple of manual focus primes in this range. I bought the pair for something like a hundred bucks plus hardware to adapt them to my camera. They're fun to use in the situations where it is feasible to do so, and if I really wanted to do some controlled (studio) portrait photography, I might pull them out, but otherwise, they are enough of a pain in the backside that a few hundred bucks is an upper bound to how much I'd pay for one.
Lack of autofocus makes a lens cheap in my mind. Sure, I can focus photos by hand, but without a really long focus throw, I'm not likely to hit the focus as precisely as an algorithm can, and with a long focus throw, I can't do it nearly as quickly. When you're doing unposed portrait photography (which is a big part of what I do when I'm touring), a half second means the difference between getting a great shot and a total dud.
So I agree with the folks saying that if this were a $4k lens with autofocus, it might be interesting, but a $4k manual focus lens is a non-starter.