Rather than using the list-style-image property, you can set some (left) padding on the li elements and apply the bullet image as a background. With this technique you could have right-aligned bullets, if you wished. :)
Those bullet points set as the background are definitely the way to go. I've noticed when using custom bullet points that Internet Explorer has a tendency to place them higher up than Mozilla Firefox do, and I'm not a fan of IE hacks. This even occurs after resetting the global margins and paddings to zero.
The man who comes back through the Door in the Wall will never be quite the same as the man who went out.