I've had my Yoder YS640 for about a year now. I bought it used from a fellow Brethren who had it for 2 years I think, and I paid about $1,600 if I remember correctly, but mine is with the comp cart and stainless shelves. I do not have the grill grates. I have not had the paint issues that Matt has, although mine lives in the heated garage. I built a quality reverse-flow stick burner myself, with an insulated firebox. I loved that thing and it produced some fantastic food. What I didn't have was the motivation to be tied down to that thing for 12 hours at a time to BBQ, so I sold it.
Now, I'm going to tell you, I subscribe to the camp of Thin Blue Smoke and a clean hot fire always. So to me that means fire is going good for about an hour or so before food goes on, and when I chuck a stick into the firebox, I leave the door open and let it catch first. I had very good luck doing this...........On my Yoder, after lighting, I let it come up to temp for about 30-45 minutes or so, until my smoke is running thin blue. I get the same result; food that is delightful and has been kissed with smoke. I use Pit Boss Pellets. I don't think my food tastes much if any different, and I definitely don't think I need a smokintube. Maybe I'm a lighter smoke type of guy, but none of my family or neighbors have ever complained. From what I know about the other brand of Pellet cookers, the Yoder performs the closest to an actual stick-burning fire.
All this to say, that if you decide on a pellet cooker, you will not be sorry with the Yoder. I sure love mine.
Whatever you decide to do, good luck!