I've seen a number of posts on the water hole... and have run 1009's and permatorque as supplied with no problems. I think that hole/slot is more of a vent than a flow passage. As far as brinelling, I think any gasket can do that with an aluminum head... especially gaskets with the heavier fire ring. It doesn't seem to be a big issue. If not serious or extreme, no problem to re-use the heads as is when pulled.