The soil you choose is VERY important. But what is just as important is HOW you use it. There are so many factors that go into choosing a medium. You cant just say use "Joe's Dirt" it worked good for me. You have to know what you are using, and how you should use it. I would stay away from any and all Miracle grow products, especially if you dont know what you are doing. Almost everyone has problems with MG.
Do you want to use a rich soil that will not require a lot of additional fertilizer? Do you want a less rich formula where you can decide what nutrients to add? You have to do enough research upfront to have SOME idea of what soil you need.
What ever soil you get your going to pretty much be stuck with it for a few months. Do you want to just try to grow once or do you want to actually learn how to grow? There is a TON of info here at RIU, including soil mix recipes. You have to learn what is that, what will this do, and what is that for? Its N-P-K (nitrogen-phosphorus-potassium) and has nothing to do with PH. What is the ideal N-P-K? Again it depends on so many other things. There is no BEST dirt. Anyone who simply tells you what dirt to use isn't really helping without also telling you exactly how to use it.
If you do a little homework here on RIU, you will find that you want a fairly rich soil with very good drainage.
Search and read about "soil conditioners". I use hyponex soil from Kmart, but i add a lot of things to it, for specific reasons. i have been tweaking my formula for 4 grows now. I could give you the exact recipe but, you really need to know the "hows" and "whys" just as much as the "whats" Do you want to be given one fish, or do you want to learn how to fish for yourself?
I'm trying to help the best way I can here, and I wish you all the luck there is.