Gosh, I really hate to do this... 9ml for $10 is not the worst price I've seen, but not a GREAT price. The majority of the vendors in the sub-forums offer juice between fourty five to nintey cents a ml.
For instance, I just ordered from Good Prophets and they are offering a free 30ml bottle on your first order from them. That worked out to about fifteen cents a ml.
Although you will pay a bit more per ml with smaller sampler sizes, it is a great way to figure out what kind of juice you will like! Also, look around at the different cartridge mods. I found that for the cartridge mods in terms of their effectiveness versus their ease of installation nothing beats the "blue foam mod" with the "pyramid tea bag" mod in second.
BTW, I just saw your post...CONGRATS on the 510! You will be MUCH more pleased with it, I am sure. I can say that with confidence, since that is the next PV I moved to after the pathetic and all too early death my Blu suffered. Lastly, please understand that I am just trying to help you, so you don't end up regretting your decision to try out a personal vaporizer!
Also, I have spent a lot of time searching out the best prices for this stuff, since my cash is extremely limited right now too. Feel free to drop me a private message any time, if you have questions!
~The e-vapangelist