I heard about this recently and decided to give it a try. The profitability charts looked really nice, for example. Anyway, here's my
24-hour review of Hash Cows vs. Litecoin. I'm going to keep it going for another day, but so far things aren't looking all that good compared to other mining options.
a) A couple of hours of down time will effect results.
b) Some coin is always waiting to mature and be exchanged (you'll be getting credits for about 3 days).
c) Mining involves variance, so any results of a comparison test that is less than 2 weeks, run side by side, is meaningless (imo).