If you have the time and space to make MTS, go for it. Otherwise, you can easily use Miracle Grow Organic Choice Potting Mix instead. I chose the latter because all you have to do is buy the bag, dump it into the tank, and cap it. Of course you'll need to watch your water parameters but it shouldn't be too much of the problem if you have to cycle your tank.
RAOK Club #77|The Fraternity of Dirt #112