the 55xx sub's are some of the best looking Rolex ever made, IMO.
I definitely dig the plexi crystal and how clean they look without the date and cyclops.
The main difference between the 5512 and the 5513 is that the 5512 was a COSC Chronometer while the 5513 was not. Different calibers were also used. I actually didn't know they had some good 5512's out there, probably the only Submariner I would buy today. I am done with the modern ones, and I am still waiting for a killer 1675
The 14060's were better a few years ago, oddly enough. Now they all seem to have maxi dials, and some even have SEL's. I do like them, but they just don't have the charm the vintage models do. I would definitely go that way, especially if you had one prior. Just remember to put it in a jar of pennies and shake it in your free time for a few days to get it looking used
Good luck, and if you do end up buying that 5512 please post phots, I would like to see it.
Take care