I've been using a gas unit for years now because of it's quick heat time as I often grill after getting home from work. I recently bought the "Duo" from Char Griller (http://www.chargriller.com/store/popup_image.php?pID=29&osCsid=16100ec3bbe509632494f5ba6a3334a2) so that I can use charcoal when I have more time on the weekends. Even though I've used charcoal BBQs before, I've never used a smoker. I noticed that Char Griller makes a side fire box for smoking (http://www.chargriller.com/store/product_info.php?cPath=22&products_id=46). Do I need an attachment like this for smoker chips to smoke meat in my new BBQ? Can't I just keep the charcoal fire down low in the main unit with the smoke chips in it? Not really sure how this works since I've never done this before. I'm kind of at a loss, but I want to do it right. Any help would be appreciated.