It seems that cheapest isn't always best when paint is involved.
The green color that was in the bathroom when we moved really didn't match our towels. No big deal. We can paint it. The tan color looked really nice for a few months and then these lovely water spots started showing up when we took a shower. At first it was just after we ran the hot water and the bathroom was steamy. Then they became permanent, yucky, mildew-y looking splotches that never went away.
Rather than having nasty looking walls we decided to buy some better paint and paint the bathroom for the second time in 11 months. Hopefully this is the last time we have to paint it unless we want to change the color.
The color is a little different but we actually like it better and there are no gross water spots! Hooray!