My first experience with them was with my Dad's back in January really liked but wasn't so sure about having to buy pellets. I then chose to buy a Cookshack Amerique and had more problems than I care to re-live (note that is not the norm for those). After that I chose to buy a Traeger 125 and have been very happy with my choice. I've tried pellets by Traeger, BBQ'rdelight and Cookinpellets.com. I like the last better than the rest I feel I get a better flavor.
I mostly cook ribs and butts although I do cook the occasional burger, steak and so on. I can get mine to about 400 degrees but not much higher. If you want high heat you might take a look the new grill that Fast Eddy is coming out with, it will be produced by Danson out of Canada. He has a picture of it at pelletcooker.com but that is it, I believe it will be on the market in September.
If you have specific questions I'm happy to try to answer them. There is a specific community out there for us Pelletheads but it does not have the traffic or depth of this forum. Good luck with your decision.