I bought one a few months ago and really like it. It's nice to flip a switch and be over 500 degrees in a handful of minutes. The temps vary with each pellet type and size. The smaller the pellets, the hotter mine seems to get. It is advertised to get to 650-ish though with some pellets it will and some it won't. Humidity seems to affect temps too; my best guess is that the pellets soak up the humidity so I keep them inside the house.
If it's not cleaned regularly, a small amount of ash can rise up but it's been minuscule at worst for me but I've read others have issues with that; I've had zero issues since I started emptying the ash tray before each use. Some pellets seem to create more ash than others.
The smoking function works very well by flipping a switch from grill to smoke. I've been grilling for 30+ years but I'm a smoking newbie, so take my critique/enthusiasm regarding smoking with a big grain of salt. At this point, I have been very happy with the smoked salmon and nuts and jerky. It uses very few pellets in smoke mode but rips through them when grilling at max, probably 11 pounds every hour or two but I've not actually quantified that.
Would I buy it again? At this point, absolutely, but there was a wee tad learning curve at first. After getting a wifi dual probe thermometer, I have become more comfortable with setting it and forgetting it except for checking my phone periodically. The installed thermometer seems quite accurate compared to my Thermoworks thermometer.
It seems solidly built but we did have to return the base during assembly because one of the drill holes in the mounting plate was off. Exchange was effortless with the local dealer. Also, I think I remember reading that not using the cover supplied with it will void the warranty as it is not designed to resist the elements without it.
I've even seen a green egg or Traeger in action (other than youtube), so can't compare.
I still have a ton to learn, but am enjoying everything, even the mistakes are tasty.