I used a clay bar last weekend and then did the Meguiars 3 step. Came out awesome. But alas, it rained like 2 days later.

The drawback to Meguiars is that it doesn't last that long (a month or so). The good thing is that it's loaded with UV protectants to prevent sun damage. There are a lot of waxes out there (like Liquid Glass) that will bead up forever and ever, but they don't have any sort of UV protectant to prevent fading. Not sure about the Rain-X wax. I just stick with Meguiars since it works. And with the orbital buffer I can wash, dry, and wax in about an hour and half total. Longer if I clay it.