The only Spanish guns I’ve owned that needed some metal work were AyA’s. Good grade guns too and all brand new, 1 owners. First was a AyA 4/53 that the forend iron developed a crack. Second was a small bore #2 with rounded bar that the ejector broke on its second outing. 3rd was another #2 that developed really bad firing pin drag, come to find out the left tumbler was also peened and misshapen. All 3 went back to NECG (warranty center at the time) and all 3 were repaired at no cost to me. I sold them soon after they were repaired. I just lost that loving feeling I suppose.
Oddly enough....the cheaper Ugartechea Model 30’s (Parker Hale & ACT imports) I owned....none of those cheap guns ever developed any issues. Same with a really nice, 1960’s vintage best grade Victor Sarasquetta that I bought from Thad Scott a really long time ago...no issues at all with that piece and I shot the hell out of that gun.