Welcome to ECF! Unlike the others, I started off with the lights (8 - 11mg) because that's what I used to smoke. I stuck with this level for about six months before I began to wean myself off the nic, altogether. If you smoked Lights, 24mg may be too much. You'll know that you've had too much when you get a headache and jittery.
Before I quit smoking, I used to spend an average of $300 per month on cigarettes. Now, I spend about $100 every other month for juice, attys and batteries. Sometimes I'll splurge if I want to try out a new brand of e-cig. But most of the time, I stick to the basics so that I can save money. So far, that's working.
This has been the best method I've used to quit smoking cigarettes. After a couple of weeks, your bronchial tubes will feel better than they have in years, and you'll be able to taste and smell again. Good luck with your journey. I hope you enjoy the e-cigarette as much as I have.