Most CPKs use gas ovens (although they look like wood ovens), some have combos but I think almost all of them use gas. Gas will not even come close to giving you the same results as a wood fired pizza. While Sammy's uses wood, it does not cook at nearly the temp. needed to give you a great pizza.
Only wood ovens that cook at extremly high temps give you the result that you are looking for. This brings up a problem for most pizzerias that it is very hard to cook pizzas in an oven that is 875-1000 degrees. You have to have a fast, talented and well trained person turning the pizzas or they will burn. You also go through a lot of wood and need someone experienced enough to keep the oven at that temp. Because of this most people do what CPK does, switch to low temp gas, or what Sammy's does, cook at low temp.
Since you mentioned CPK and Sammys I figure you are probably in California. If you are in Southern California I would go to Antica Pizzeria in Marina Del Rey to see what wood fired pizza is all about. I know he cooks at a minimum of 850 degrees, uses great Italian flour and tomatoes and makes his own fresh mozzerella.
I promise you will see what all the fuss of wood fired ovens is if you try a pizza there.