In aikido, we will always push the refinement of our techniques well beyond crude effectiveness, and it's this constant refinement that is the art of aikido. Just make up your mind, and come to the dojo. For those who would feel more comfortable to start with a group of other beginners, we have introductory classes starting every two months or so. I study both, because they both appeal to me. After a while, you realize you can't do an energetic form of aikido every day, so I like to alternate days of zazen with aikido.
Most students stick with one or the other.
Let me say, though, I do believe that everyone can benefit from making a genuine commitment to some form of continual learning, preferably in a group setting. Aikido and Zen just happen to fit the bill for me. Zen is unique in its ability to test your commitment and to help you view the world a little differently. At their roots, aikido and Zen are really both about recapturing that innate capacity for happiness.