Anyone have any first-hand experience with Katz Eye focusing screens?

[USMCWayne]

I'm intriqued by the after market focusing screen offered by Katz Eye, especially the one with grid lines, and wonder if anyone has any hands on experience with the product?

I used something similar on my old F1, and recall it being pretty handy for keeping horizons level, but that was strictly manual focus.

If, as advertised, "The screen will have NO effect on the functioning of the autofocus sensors of the camera and the AF point indicators will continue to function as normal" it seems the almost perfect 30d modification.

Katz Eye does note partial and spot metering is affected with their screen, but I can live with that and adjust as necessary.

http://www.katzeyeoptics.com/item--Canon-30D-Focusing-Screen--prod_30D.html

[Wilt]

Better to upgrade to 40D and change out the standard screen with the Canon EF-D screen and use the CFn to permit the camera to correct out any errors in metering due to the focusing screen!

I don't know that anyone has found a specific correction for the Katz Eye that works in all cases...the correction may depend on the max aperture of the lens or other factors. Must users simply use the 'I use Evaluative' as the reason to ignore the issue. Some users on POTN have reported up to a 3EV error in metering.

[Tdragone]

I have a Katz eye in one of my 30D's and LOVE it (I took it out of my 20D when I sold that)

I'd have to say when spot metering with my screen (Mine has the brite treatment or whatever it's called) it's off by no more than 1/3 stop. NO WAY it's near 3 stops!

They note the possibility of a blackout as you approach F8; and with my 100-400 + 1.4 + a borrowed 2x it showed no signs of having a problem.. so I see no reason to avoid it!