A person with full myth and no allagan is trash. Needs to have more than 2 pieces of allagan equipped to be good.
Actually this isn't that far from the truth, despite everyone picking on this post. Drops from T1 and T4 actually suggest that you know how to play your class. Drops from T2... well, they indicate nothing at the moment.

And yeah, the vast majority of people with Allagan weapons are more than likely quite skilled players.

Being i90 doesn't mean too much, the quality of the drops you have does though.