I'm going to be upgrading my gear set soon, and I'm torn between the D610 and the D750. I was basically sold on the 610 until I started reading reviews about the oil spot dilemma. Is this still a problem with them, does anyone know? Really, all of the things that make the 750 better than the 610 aren't things I use that much or they don't make enough of a difference to justify. But, if the 750 has a better track record for not having problems than the 610, I'd make the splurge. Advice, please?