Somewhat true, for the market can go in cycle or shift. If you read my last quote to DarkKnight:
True, but if you bought any big keys before 2008 you are doing just fine. An example, if you bought a SC22 in 2010-2012, you were under performing not until the later of 2015 . But again, the market is so "first appearance" driven now, so group of characters forming a team; such, as Avengers 1 or BB28 doesn't have the appeal as it use to. On the other hand, Fantastic Four 1 and X-men 1 contains many first appearances which out shines Avengers 1 or BB28. Another example would be X-Men 94 which lost a lot of luster to Giant-Size X-Men 1 and Hulk 181.