Since no one else has answered - generally speaking in Spanish top grade guns:
The wood to metal fit is superb
The metal to metal fit is superb. It is often difficult
to see the joints - say between the locks and the action.
The engraving is near 100% coverage and symetrical.
Frequently the locks are gold plated
The rib is hand filed
The checkering if very fine - both in quality and lines per inch
Rolled edge on the triggerguard
The barrels are struck very well. When you look down them you don't see highs and lows from a polishing wheel.
You might email Arrizabalaga and see what they tell you about the gun.
Here is their website:
http://www.pedroarrizabalaga.net/PRESENTACI%D3N.htmAnd here is their email address from the website:
pedroarrizabalaga@pedroarrizabalaga.net
Best,
Mike