I really think that the rule should be 90%.

It's always seemed to me that in order be #1 a set should truely be complete. The registry points are an arbitrary system designed by a group of people that thought they knew the best way to rank coin sets using a function of (supposedly) multiple variables. I've never seen their algorithm and it may be the best ranking system that can be realistically achieved, but it may not be. However, no matter the case, it is extremely short sighted to say that 1 or 2 coins is better than a nearly complete (or complete) set based on some arbitrary system.

Personally, I've never really subscribed to the whole top coin for top dollar philosophy, at least in the the context put forth by others. I believe in buying what I feel is a nice coin for what I feel is a nice price. I collect mostly Moderns at the moment, and for me the best coin is rarely the MS70. I like MS69s. Not only are they significantly cheaper and kinder to my college student budget, but I think having at least 1 or 2 flaws can be good for just about anything. It's the little flaws that make us who we are. It's the little flaws the make my 69's slightly different from every other coin. Does it really matter that I can pay two or three times the price and get a "perfect" (according to who?) coin that gets me 10 times as many registry points (big whoopy!). When I started collecting I actually thought that MS70s were a myth since perfection is a scientific and engineering impossibility, then I found out people had MS70s! Funny thing being? They're only flawless up to 5x magnification. I'm a Chemical Engineering major and I'm being taught to think on the atomic level (care to guess how many flaws there are in your "perfect" coins?). In all fairness though, I do have 1 MS70, purchased for a special and specific reason.