I struggled with my decision to buy a pellet grill, and after buying it am loving it. However, there are some shortcomings that you should be aware of.
The main difference between a pellet grill such as my Traeger or others such Green Mountain Grills, Pit Boss and a gas unit such as a Weber or Broil King can be summed up as...the pellet grills are designed for low and slow cooking, and can smoke whatever you are putting in them. They are like an outdoor oven. The gas barbecues are more designed for medium heat and higher and are better for searing. They are more like a gas stove top. With new technology however, the lines are becoming blurred.