1D MKII focusing screen decision?

I need to purchase a focusing screen to be used with my Zeiss manual focus lens.

Zeiss recommends the following:

EC-A Screen
http://www.bhphotovide​o.com …EC_A_Focusing_S​creen.html

or

EC-B Screen
http://www.bhphotovide​o.com …EC_B_Focusing_S​creen.html

Does anyone have any experience with these? The EC-A is recommended for faster lenses and the Zeiss is a 1.4 so would this be a better choice?

Any input is appreciated.
DBRUN

I have the EC-B for my Pentax M42 and it works well. Admittedly, it can be tough with moving objects (like 7 month olds), because your trying to pick some vertical feature to line up, but its excellent for stationary objects.

I was running with an EC-B for a while, because it was what I was used to using on my old AE-1. The problem is that you need a perpendicular line (or close) and you can only focus in the centre and recompose, which doesn't work so well with fast apertures. In addition, because modern DSLR's sacrifice a lot of viewfinder light for the AF system, the viewfinders are so bloody dark compared to what they used to be in the Manual Focus days. This was making my EC-b split prism turn black when the light was really poor.

I finally went with the EC-s screen and like it much better! It's not great for viewfinder brightness, but at least it lets you use ANY point in the viewfinder to focus on. There are no splits or grids or anything, but it's much more obvious when something is out of focus due to the extra matte.

O.K. that makes sense, it looks like the EC-B screen may be out of the equation. I will definately consider the EC-S or EC-A. Thanks folks, any more opinions?

EC-A is the full time screen. The microprism is much easier to focus than a split screen for all the above reasons. The EC-S would be better for focusing off-center subjects, I would think.since the whole screen is a "focusing aid"

Well it looks like the EC-A is out of the question because I lose evaluative and spot metering. So that leaves me with the EC-S or possibly the EC-N?

It was brought to my attention that my exposure may be affected by the EC-S? Is anyone with a 1D MKII using this and could they describe what affects I will have to correct.

Thanks.