Yes, AE prism user on a Mamiya 645 Pro. A bit heavier than a WLF but built-in metering and a bright non-reversed/flipped view that makes it fairly easy to focus. Plus no issue shooting in the vertical/portrait orientation. The few times I looked down into a WLF on a RB67 and a Yashica TLR, I found the image very dim and had a hard time focusing although I have to say that these occasions were indoors.