Originally posted by GeneV I doubt that the optics are too far different, since it appears to be the same design.
For now, I guess I can accept a slightly larger body and use the DA40 with a Superprogram to get a 40mm on film perspective.
it does seem to be the same design but some say that the shape of the rear element changed a bit. By side by side comparisons I've seen, the M40 is not shabby but not as good as DA40 in terms of OOF and sharpness. If you don't need aperture ring, than just slap your DA40 on film body, it'll work just fine (to clarify that it is if you have film camera capable of controlling the aperture).
as for the opinion that M40 is worth only for collectors, well, I don't think it's that bad... and as for the price? Well in UK they go for £75-£150... in other words, nowhere near that of DA40 used or new...