I did find myself checking the temp too much. It really does hold well once you get it dialed in.
I too get my wood from Berry Bro's. I cut them into fist size chunks with a chop saw. I put two in yesterday with the chicken, but pulled one out because there was too much smoke billowing out. With just one chunk, it settled down quite a bit.
I'm very pleased with this cooker, and can't wait to compete with it.
I spent a lot of time yesterday monitoring the temperature too. I think it was due to the fact that I'm new to the WSM and wanted to gauge how it responded to changes and also just due to habit as an offset can get away from you quickly if you don't pay close attention. I used a candy thermometer through the top vent to monitor the dome temps and, as you can see in one of the pictures above, I placed a probe thermometer through a chunk of wood and placed it on the top grate to monitor the temperature there. After making sure that the thermometers were both reading accurately, I saw that the top grate temp runs about 30∞F cooler than the dome temp. I didn't measure temps at the bottom grate but learned of a device that might help with that. More on that below...
I, too, cut the smoke wood into smaller chunks and was very pleased with the amount of smoke being produced by using one chunk at a time. I found that each chunk would last about 90 minutes. As I mentioned earlier, I was using El Diablo lump as my fuel for heat. I started two fully lit chimneys of lump at the start of the cook and it was still going strong many hours later. Like you, I really like this unit and think it's going to make competing much less stressful. I'm certain that we'll be purchasing at least one more before Lake Pleasant in November.
Now, as for the temperature measuring help, I found a link to a couple of sites that sell grommets that you use in place of on of the screws that hold the grill straps up on the WSM. If I understand it correctly, once these grommets are in place you can insert a probe thermometer through them and the probe will then be right below the top and bottom grates. This looks like a very easy modification and much more appealing than drilling a hole in the WSM in order to insert a permanent gauge. Here are images and links to a couple of places that sell the grommets.
http://secure.thebbqguru.com/Produc...6&idproduct=136http://rocksbarbque.com/Accessories.html