Opinions on heads please?

Well if you are going to nit pick it's .5237333333333333333 which would round off to .524. :)

I guess my fat fingers missed the 4 the first time!

Hasn't been discussed but the additional rocker ratio will increase the cams duration @ 0.050. With the XE cams having very steep ramps to start with it will likely only be a degree or two.