Getting a small tattoo?

I was thinking about getting a REALLY small tattoo somewhere. just quotation marks with a space in between them (like "____" sans underscore. it's a long story. :P) But I've heard somewhere that small tattoos become muddy and stuff over time. I don't want mine to look like that as I age! Does anyone have any tips on the smallest possible size I could get? It wouldn't be text or a picture or anything, just small quotation marks,