The question is a bit misleading first its important to choose a serious gemology laboratory report and only then compare the different parameters such has clarity.
I think that if you want to be 100% sure that your diamond won't disappoint you then choose a VVS diamond, but most of us don't have the extra budget that VVS costs, so take a VS diamond but
look for VS that the imperfections are on the side that way with a professional setting the imperfections wont be noticeable.
I suggest avoiding I1 I2 I3 diamonds as center diamond although they are much cheaper the reason is these flaws are easily noticeable and prune to damage (if you didn't know diamonds might be the hardest material in nature but it doesn't make it unbreakable.
Hope I helped

Post edited by: david, at: 2007/11/24 17:41