I normally use Walmart paint. It's a lot cheaper (only $13 per gallon) and it has generally held up well but on occasion it's very frustrating. Like this week.
We picked out two colors of blue for the living room. This room (including the attached entry way and halls) is using 8 gallons of paint. Seriously. 8 GALLONS. Anyway, we got a couple of sample cans to figure out where we want the lighter blue and where we want the dark blue. We picked one large wall and the upstairs hallway for the dark blue. Well it turns out that when mixing the quart cans Walmart's fandeck match is correct and we get the right blue. When mixed in gallons, rather than say it can't do that, it makes purple.
The red circle is the gallon size, the blue circle the quart size. Do they look like the same color to you? Because apparently WalMart thinks they're the same.
Unfortunately we had already painted the upstairs hallway (don't mind the bad cut-in or the unfinished picture in the middle) by the time we discovered this (thinking it would dry differently) so as you can see the room now has a purple wall. Dammit!
So now we have to either buy 8 quarts instead of two gallons (at a really stupid price) or go try the color matcher somewhere else since I already had the room cut in with the right blue and I am NOT climbing up a 20' ladder for 2 hours again. In the meantime my living room looks like a serious bomb went off. Argh!