I know that those mugs can be easily made on certain websites, and the damn websites only offer them in white, but for what's it's worth, I think the mugs should be brown. Bitbrew seems like a brown color business, to me.
You know what else is brown? Feces. Speaking of feces, that first heart design...... Nevermind
I like the second design, only if it was inverted with black being brown.
On that note, my instincts tell me that this is the kind of thing you should be giving away to your customers, not selling, and that they will end up in Goodwill in the near future.