Most chicken taste the same, I have discovered that they seem to get more tasty if you slaughter later. With most breeds i try to keep the birds until 12 or 13 weeks old. But the longer you keep them the tougher the meet gets, you wouldn't want to keep a white rock until it was 13 weeks, you'd be chewing on rubber. Over the years i have settled on 8 weeks for most birds and i get a nice compromise of flavor and texture. I have to say, of all the different breeds I've ever slaughtered, the Cochin is the best flavor, and you can slaughter much later without the worry of tough meat.