They're offering a nice APR on zing currently as well which will change when opening becomes available to reflect the rarity of the items and creatures you've received!
I.e. if you get a really rare creature you'll earn way more collection rewards for it compared to a lower rarity one. The way it's now all vials give you the same rewards, it only matters how many you own.
and then once capturing is available and crafting, those will count towards your collection earnings too so it'll dilute all vial holders over time!
Nice. Bought another one for the collection and looking forward to playing after the stacking!
good luck! I've bought way too many at low hive prices, need to wait a bit for hive to go up before I buy any more lol.