I purchased the
Marware Sport Suit Relay armband when it was released, and have been using it for about 2 weeks. I'd definitely recommend it. I previously used the Nike armband and did not like it at all. The Marware is comfortable, light, protects the iPod, and allows me to use it on my wrist or bicep. The velcro is secure and I am not too worried about it falling out. The addition of the Nike+ transmitter pouch is a plus, since I do not use Nike shoes to run with.
The only issue I have had with it is the plastic "fogging" up when I am on a longer run. I don't know if this is caused by outside moisture getting into the pouch area, or because of the heat from my arm. But, it doesn't affect the usability of the armband at all.