I'm thinking of getting the "M" screen for my A900, but I'm unsure how well it works with slower lenses.
I'd like to use it for my Pentax M* 400/4 & 800/6.7 lenses on the A900.
I have no trouble focusing them on my 67II, but find shooting moving subjects nearly impossible on the A900. Static subjects are no problem.
They will be used in good light (Hawaiian sun), to shoot our large winter surf. Thanks for the help.