The going "wisdom" on colored tops is, don't select your HGH by the color of the top. It is generally used to identify generic HGH but what you want to do is find a VERY reputable supplier first and then choose one of his "colors". Blue tops are normally a Chinese generic that is commonly sold from the best suppliers but most people will tell you that it is 192aa. I've seen reports of welps and redness after injection which many attribute to the antibodies fighting the 192aa HGH.
Brown tops are now branded as Hygetropin (not Hygentropin) and there are very few reports (if any) of reactions at the injection site. Hygetropin (Hygene Pharm) is reported to be run by one of the top dogs (a scientist or something) that used to work for Jintropin. Hygetropin and the suppliers I know of swear that it is 191aa but the jury is still out as a very reputable board moderator is saying it's 192aa. He hasn't provided proof yet. I just started with Hygetropin and have no welps or redness.
Incidentally, my brown top Hygetropin has blue tops. It's the 8iu vial variant of the Hygetropin HGH. Not to be confused with the "Blue Top" generic.