I clay barred my car today and what a difference! The body used to feel like fine sandpaper if I ran my hand along it, espeically the hood, roof and trunk. Now the whole car is smooth as silk, feels like a brand new car. Now it's ready for some spring wax.
I highly recommend everyone do this to their car. Our cars are pretty old,. so most of them need a good cleaning. It was really easy to use the clay bar, just make sure you put a lot of lubricant on the car. I got a small scuff on the trunk lid where I didn't have enough.
The kit only cost $20 and it took about 3 hours (wash, dry, clay bar, wash, dry)
Here's a pic although it's pretty bad and hard to see anything in terms of cleanliness.