I am by no means an expert, having only smoked chicken a few times (just got my smoker a couple months back), but here is what I found. Low and slow makes for really tough chicken. I settled on 325 degrees for about 2 hours with the spatchcoked. Just be sure to check the internal temperature at about 1.5 hours...cook time varies by mass. To get that temperature, I use one chimney load of Kingsford competition poured over 2 chunks of peach wood (maybe 12oz). Apple works great too. I do need to prop open the access door at the half-way point to keep the temperature up. I also brine the chicken for two hours in salt/table sugar. You end up with fairly crisp skin, and very moist flesh. Really this is the same as I have done for years on the grill (temp, time, brine) and it has always worked great. As for skinless breasts...I can't help you there as I would only try it on the grill at a high temperature. I don't eat the skin, but I think you get better flavor and a more moist finished product cooking with the skin on and with the bones still attached.