I have used the 5x8 pellet tray in my FEC100 several times. The best results that I have found is to turn the FEC on but not start it, the small draft caused by the slow fan helps. You REALLY need to make sure you get it started well before you close the smoker up. I use a a chefs torch to really get it going well and have a good bed of embers. The tray lasts a lot longer than the tube for me (I have both).