It's difficult to compare the guilloché NY to enamel dial. Their similarity stops at they are both WT.
There are so many personal feelings that goes into the NY dials for US collectors and people with connections to NY. If you do not have any connections to NYC/US, maybe this watch will not appeal to you at all. We don't need to mention about the 5131's appeal. I am sure 99% of the PuristS on this forum would agree the 5131 series is stunning!
For me personally, I will have to see the 5230NY in metal to make a fair assessment but the 5230NY has a special place in my heart because I am from the US and any watch from NYC exhibition appeals to me but the 5131 dial is mesmerizing. I will not be able to pick which one I "prefer or better than the other". It depends on the occasion to pick a watch that best suits me.
I know this is a disappointing answer but I just can't pick. Hopefully, I can give a better assessment after receiving mine. 
KC



