I've put about 2 tanks of gas through and all is good so I'll do a quick summary before I start to forget.
The quality looks excellent and even the seals/gaskets look and feel as good or even better than the OE ones.
The metal cover has serviceable PCV valve and baffle passages, I was going to unscrew those to look further but I did not.
The metal cover uses bosses to control the gasket crush so does not use sleeves, comes with new bolts and no spark plug tubes needed.
One thing to watch for is that the head has 2 outside corner dowels which need to be removed because the replacement cover is not machined for them (or the spacer sleeves,) the 2 inside dowels stay but make sure that the cover is sitting on them properly and flat on the gasket before bolting in down.
The mounting bracket for the back of the valvetronic motor is improved and uses a female hex head bolt which is really nice to get to especially with a ball end allen/hex wrench. The other 4 bolts to hold in the valvetronic (and gasket) are changed to female hex as well.