To answer your question,both cases are similar in construction
The Euromariner has a small gap inside the retaining Ring for
a small gasket. This gap is not needed any more after Chris has
updated the Crystal with a Clark's one.
Casetube is bad on the older Euros I don't know if it's updated.
Crown looks nice.
Euromariner has a Noondial installed also a Noob datewheel.
Bracelet is also from a Noobmariner.
The WM9 has no gap inside the retaining Ring that's right.
The Dial is better now has SL applied on the markets and Hands.
The datewindow is also better.
Date wheel is also better.
Also the Bezel insert is better on the WM9 Pearl looks really good
CG's are better also the Tube, Crown is a bit oversized.
The Bracelet is not bad but George updated it know because
it needs better shaped SEL's.
All in all the WM9 is better in my opinion, the best Sub out of the Box.
With some Mods the Euro is also a nice watch and near to the WM9 but
You must invest some money and work.
You can get the Euro only from Chris.
PT has the supreme Sub ( I think it's the WM9 V1)
Hope this helps.