Hello Paul,
The question come up a lot around here. The best advice is to go along to a class or two at each dojo and see which class you like the most.
The Dojo that I train at has three Aikido styles and the one I pratice I really like because it is a good effective form of Aikido, and also (very important) the class is laid back and all the ppl are really friendly and good fun to train with.
Jeremy.
www.aikido-dynamic.co.uk