My dad has one and I've cooked on it a few times. It's fine for what it is (a budget friendly pellet grill with few bell and whistles). His hasn't had any issues and never had to reach out for customer service stuff, so I can't really comment there, but it's held up well fora a grill that's semi covered by a patio but still mostly exposed to the elements. His is one of their most basic grills, and some of their newer stuff looks dang nice and has pretty decent reviews online and on YouTube.
I will have them on my short list when it comes time to replace my current pellet grill. I almost pulled the trigger on a 600D3E on Black Friday. It was like $300, but I couldn't justify it because my current set up is still working ok…still kinda wish I would have done it… good news: they're ALWAYS running some kind of sale, so if the one you're looking at isn't on sale, wait a couple weeks.