eh.. I have never hit bottem with a pigment and I honestly love it for that. because with my eyeshadows it was "replace every 4 months" and respend that amount again and keep doing it if you want to use that eyeshadow, what I feel the great thing about pigments is, its dubble the amount down for the eyehadow but you get about a million times the product for an unbeatable price!
I have had friends that also love mac go into a pro store together because they want half jars and split the pigments and glitters in half, that way its half the price for them and half the amount.
also for those that spill (or want a sifter top), I thought I would share. I have tons of pigments never spilled a jar because I've never used them out of a jar, I thought I would have the same problem with spilling, I got a ton of the sample size jars at mac -just ask for them- and pour or measure in a small amount and use it from there... so if you do spill its not as bad or as costly to replace and at the same time keeping your pigments from gettin a brush dipped directly into one...
or you can buy the siffter jars from mac -they are sold at mac pro stores- pour your pigment in there and use from there if you want the jar with the sifter, ya.. a little more work but you get what you want.