I asked myself the same question, and my answer was to piece it together. If I had the money, I'd buy it all at once, but if ya cant get the rims first, it'll motivate you to hurry up and get the tires.
The Yoko's i had for a good few months. I noticed they gripped much better right off the bat compared to stock, and definitely handled well in the rain. I sold em to another member on the east coast who was gonna use it for winter..