I've finally come around on baking stones.
Early on, when I first started this site, I really didn't see the value of baking stones. They seemed to give a little extra pop to my loaves, but the difference seemed inconsequential.
I think I was doing a couple of things wrong. For one, I wasn't preheating my baking stone for long, and I was only heating it to my final baking temperature, typically no more than 400 degrees (see lesson one to see what I am talking about). Only preheating your baking stone for 15 or 20 minutes and only to 375 degrees is not enough to make much of a difference.
I also was initially using cheap, thin baking stones that didn't retain much heat. To really see the difference you need something more substantial.
So here is what you should do: get a substantial baking stone. You can buy one relatively inexpensively, or you can making one out of bricks or unglazed quarry tiles, which are extremely inexpensive and can be found at any home improvement shop. Place the stone in your oven at least an hour before baking and turn the temperature WAY up to 500 or 550 degrees, whatever is the maximum temperature your oven can safely go. Let the stone get EXTREMELY hot before placing your bread on it. If you do this you'll get much better oven spring and really notice the difference between bread baked on a baking sheet and bread baked on a stone.
I've been so happy with the results of my baking stone that I am currently experimenting with using a stone both above and below my loaves, to see if even more radiant heat will increase the spring.
No verdict yet.