****Update 12/2014: So I finally found something negative to report. Today I was cooking 2 pork butts and a brisket and discovered that this grill does not do well with wind on a brisk day (It was 45 degrees here today). When set at 250 degree, the smoker could barely make it up to 190 degrees. I was able to bypass the problem by throwing a cheap moving blanket over the grill (an $8 fix) but I think it's worth noting.
You’re concerned with ongoing costs for fuel and power: The wood pellets used with Traeger grills are more expensive than propane or charcoal. You can expect to spend $1 to $3 per grilling session using wood pellets. Propane is far less expensive to operate in a grill, while charcoal fits somewhere in the middle of the cost range. And beware of cheap pellets from third-party manufacturers that contain softwoods like pine. They burn much faster than hardwoods, so the end cost won’t be that much different because you’ll use more of them. And they can introduce unwanted chemicals and contaminants to your food. You will also have some electrical power costs with these Traeger pellet grills.
In 2010, I sprung for a discounted Rainer with $80 in tip money and a pro deal through the whitewater rafting company I worked for. It was an expensive purchase for me at a time when my monthly food budget was around $60. But hey, along with a Roll-a-Table, two chairs I “borrowed” from the rafting company, and my cooler, I had almost a full kitchen that I could deploy from the back of my truck. And the Rainier quickly proved a wise investment.
Although these are marketed as grills, they do much more, including baking or roasting. Because they heat by convection, you might not get the grill marks that a gas or charcoal grill will give you, but you also won’t have the flame-up problems. While many pellet grills offer high cooking temperatures, the maximum depends on ambient temperature and wind. Many users wrap their grills in special insulating covers to help maintain heat, reduce fuel use, and reach the higher temperatures they desire.