I've been a long time Meguiar's user and I'd suggest going with all Meguiar's products. I've been using them for a LONG time (I just won the April grand prize on their forum)
The other guys are right about getting what you pay for. Do NOT skimp on your products!
If you have a D/A polisher, something along the lines of the Porter Cable 7424, you'll save yourself a lot of time cleaning and detailing your car.
Here's what I'm going to do to mine when I get all the products in from Meguiar's.
1. Wash the car using the two bucket method.
2. Clay bar
3. Polish to get rid of the spider web/ swirls out of the paint
4. Top it off with two coats of quality wax.
You won't believe all the contaminants that will come off your car with using the clay bar!
I can't wait to see what it looks like using the 'good' stuff from Meguiar's.