As an old desert rat, I have eaten rattlesnake a few times. The meat does "taste like chicken," but snake blood has a very strong and distinct smell and flavor that affects the taste of the meat. If the snake is not properly cleaned, it will not be pleasant.
Would I eat again? For survival, sure. Just because? Maybe. If something else is available, I would probably pass on the snake. It's one of those things you should do at least once in your life. Do it, get the t-shirt, and move on to the next thing on your bucket list.