I didn't get the AE prism, just the metering PD prism, but I don't use AE much in 35mm either and it should be a wash in that respect. I think my hit rate is mostly limited by the psychology of shooting different formats rather than by exposure---you know how one burns 35mm film casually and is a little more careful with MF film, more careful still with sheets, and I don't know how I'll end up handling 645 in practice. Even if I end up spending more per keeper, the extra image real estate seems like it'll be worth it, and I like the 3x4 aspect ratio better than 2x3 for most purposes anyway. Thanks, you shameless enabler. :-)