Consortium Dye Kit?
Stormïe ~ Tarnished Coast | My little monster <3 – http://valid.canardpc.com/6nbdeq
if they are like the halloween kits, yes. It would be cheaper to just convert your gems and buy the specific dyes you want than to gamble.
These do not contain new dyes. You are guaranteed to get 1 random blue dye and 1 random yellow dye. They might be ones you have not yet unlocked, but if you have unlocked them you can always sell them to buy other dyes, put them into the Mystic Forge, or give them to one of your alts.
i opened 3 of these things today and I only got 1 yellow dye. I want my gems back. =/
Yellow and blue are the hues of the dyes, not a reference to their rarity.