Actually, just about the best chai at all comes from The Masala Chai company in Santa Cruz. It is that perfect blend of complex spiciness with a nice "bite." It was my first introduction to tea in the late 80's and it has spoiled me for all other commercial chai's--so much so that no matter how i LOVE chai, I gave it up altogether when I moved to the NW (sorry Oregon Chai), and couldn't find a decent cup anywhere.
You'll want to buy the "Masala Chai Spice" under the "Bulk Tea and Spice" section of the Products page. It's the only commercial chai I've found that actually has the right instructions--you boil the spices to extract their flavor, then add the tea at the end, steep appropriately and strain. They do now sell a liquid version that you can add your own milk to (3 pts chai to 1 pt milk to keep it as strong as it should be).
My mom sends me a box now and then to keep me from completely forgetting how great it really is. Check it out.