Herge,
There are a number of threads addressing impact on AF and AE. Here is a link to
google result.
The main thing to be aware of is the loss of center spot metering. I have not experience degradation to AF. But black out do occur at f5.6 of higher.
Unlike jinfinance, ebay seller shoot-ing ship with finger cots and tweezer, albeit for $3 additional cost. I bought from shoot-ing first for a k100D screen, then from jinfinance for a diagonal split screen for K10D.
Although the problem that started this thread have been resolved, jinfinance has yet to reply to my original complaint. This leaves with me with a very negative impression. I will wait another day to give him a final chance to respond before I give my ebay feedback, you can be sure it will not be a glowing commendation.