Nice write up, thanks for that.
Regarding the inline vs flat thing, i was talking with my mate who works at a big subaru dealership on the subject. Yep, sure, changing spark plugs, rocker gaskets, or any of those things on the head - they have the box beat hands down. But for pretty much everything else, he said subaru's are such a breeze to work on. He used to work at a few other places, but once he moved to subaru, he's not going anywhere else