Excellent. You won't be sorry. The initial expense of vaping seems high, but once you start filling carts and find the right juices, you'll save a ton of money over smoking.
One thing though, I hope you like that menthol fro Pennys. 40ml is a lot. Usually, it's advisable to get 10ml, or even 5ml bottles until you know for sure you like the juice. I don't mean to complicate things, but it sucks to be stuck with a juice you don't like, and menthol is particularly tricky for a juice maker to please everyone with.
If you like the menthol of Blu, it's probably pretty close to the Volt menthol. JC makes juice for both of those companies. It might be better to get your replacement menthol juice from Smokeless Image. Then, maybe get a smaller quantity from Penny's.
Or, get 2 bottle of juice from SI, one 12 and one 18mg. Then, get 4 boxes of blank cartomizers and fill them all. That would probably be the most economical way to do it without risking getting stuck with a menthol you hate.