You are going to love your WSM!! Got mine a few months ago and I am so happy with my purchase! Danny is right about temp control, and can be quite challenging with a brand new WSM. I tried pork butt for my first smoke on mine...started it at 2:30am, figuring I would go back to bed after I got the temperature regulated...but never ended up getting any sleep because the temps kept bouncing up and down.
Second smoke went much easier and was able to regulate my temps much better (still not confident enough to step away for more then an hour though) LOL
As for whole chicken, I smoked some this past weekend however I smoked mine at 235 for about 3 hours (I also brined it over night and injected it)...I wanted to see how juicy and smokey I could make it with a nice slow smoke. During my smoke I used up about 4 chunks of hickory and 2 or 3 chunks of apple. It definitely had a nice smokey flavor to it.
I might try a higher temp next time to really see for myself the differences. I did miss not having a nice crisp skin...guess I could have tossed it on the grill for a bit, but we were too hungry!
Good luck with the new smoker and your first smoke!!