You'll get more different answers than there are products available.

With that, anything solvent based will shrink. Period. How much is dependent on the solvents and base materials, and how long you let it cure. If you can let it set, you can sand out any shrinkage with time.

2 products I've used with great success:
Clausen All-U-Need: http://www.smartshoppersinc.com/AutomotiveFinishes/Clausen_Primer.html

Tamco: http://www.tamcopaint.com/hpdtmgr2kprw.html


They are 2 completely different products, both have had great results.

And I NEVER use one system beginning to end, so let the nay-saying begin.