The DB I bought only came with the meat probe and at first I was very pleased with it. After about a year I was getting wildly fluctuating and inaccurate readings. I called the company and there were very polite and sent me another probe. It really did not work and I presumed there might be a problem with the electronics built in. I think they would have replaced that as well but at the same time I started to compare a few of the cooking thermometers I own and found them to vary greatly.
After that discovery I put two oven thermometers in to check the temp setting at I've found it's off by about 20 degrees and at lower temps even more
At that point I did a search for more professional instruments. Thermoworks is a popular brand and I bought a quick read (just under $100- not inexpensive but for my compulsive nature very worth the money). I am getting ready to invest in one that has cables and checks both the meat temp and the temp of the cook box. That will cost about $125 but again for all our cooking we do (Wife is an excellent cook) I think it will be worth it.
I have one more comment. From the time I bought this I found that things tended to cook faster than recipes suggested. I'm not sure if this has anything to do with an inaccurate cookbox temp ( this was before my obsession with temperatures), but a representative at GMG said that pellet smokers tended to cook more like a convection oven. I only mention this so that you are aware in the beginning.
I summery- for the smoking I do-- I think GMG is excellent and I'd buy it again.
As to the wood- I guess I'm lazy. The stock woods give me good results, but I do know other brand pellets work.
Hope this helps, Nice chatting with you- Aren't smoked meats great? Just finishing up 4 pounds of Pastrami I did for a Party last week.