I just bought a smoker from Lowe's (Listed below -- the BBQ Grillware one) and have had the same problem. I was using the built in cast-iron box.... well, that didn't work as good. I packed it too tight, and didn't get enough smoke. I lessened, and was getting only charred chips...
I moved it off of the 'rack' it was on a few inches above the flame, and it was closer, and started burning better.
It was frustrating the hell out of me when I overpacked my soaked wood chips this last time again, and couldn't get smoke going for a while. So, after burning up one oven mitt, I took the #(#($@! cast iron box out and replaced with a big coffee can right on top of the burner. OK. This worked awesome. For a little while. The problem was that they burned almost TOO fast. As I'm adjusting the flame later, I see the flame lipping AROUND the can, and soon after, I realize it actually boiled all the water out of my water pan. TWICE.
I used about 2 normal sized bags of chips for smoking a shoulder for 13 hours, the last of the time, I was moreso 'cooking' it, not smoking it.
Needless to say, even though I had a good deal of smoke for a while, my smoke ring on the shoulder was less than desireable. Now, the chicken came out awesome!
So, what I'm hearing is the disposable aluminum pans are the best to use? Obviously, I'll move to chunks next time.
I had no problem keeping this between 200-250.... most of the time it was actually BELOW 225..... probably why it took so long to get to 200 degrees on the meat.
Open for thoughts. How long would a pan last to smoke with? Wouldn't the heat kill it pretty quick?
Oh, and I'll go post in the roll call :)