I had achilles tendinitis so bad I was ready to quit tennis. My podiatrist tried many solutions, nothing worked. My achilles tendons looked like sausages even with ice and advil. I had many pairs of Nike Vapors and Ballistecs, even BF II's.
A friend of mine said I should try ASICS, that they were very comfy. So I bought a pair of Gel Resolution 4's. 3 weeks later my achilles were back to normal. I didn't change anything else. It still is hard for me to believe the improvement but I'm not complaining and no I don't work for Asics. I think that the airbags in the Nike's somehow flex and allow my achilles to move abnormally upon contact with the court. Anyhow take it for what it's worth.