I think all styles should be dated. It would be easier than trying to remember Allen's secret code for saint somewhere bottles (brown bottle with black cage = drink now). I always end up drinking the wrong one and sitting on the one I should've drank, haha
Brown bottle with gold cage is drinking very well right now! I haven't tried a green bottle in a while, it does suck to open a $10 bottle prematurely. Every bottle should be dated.