I would think that the PG grills are least prone to grease fires because it is so hot right over the firepot that the grease disappears.  I'm sure those that have one would share their real life stories.

I have the PG500 but have rarely grilled in zone 1.  When I did, I didn't find grease in the tray below the fire pot.

I sometimes sear a roast there but that doesn't make much grease.

I saw the product announcement video.  What else is there to do when your retired and have a bad cold?  The video spent a lot of time dwelling on making good food for family and friends.  Features I noted on the new offerings are:

1. DC motors on both the auger and draft fan for better control.  The auger motor has auto-reverse on jam.  The draft fan looks like a standard computer fan from the diagrams.  It reminds me of the AC one the Savannah Stoker folks are selling.
2. Fuel level sensing with out of fuel notification via text messaging.
3. Turbo mode for fast heat up.
4. Departure from a barrel shape on some models to provide a larger upper shelf.  Flat sides and rounded top and bottom.   

I spent my morning in the local hardware store and they had the new Traeger pits.  I got to take apart the one Ironwood they had and it was surprised to find that the sheet metal is still about 16 to 18 gauge.  All the SS liners inside were just as thin.  The drip tray is similar.  The diffuser was strange as it is SS but very thin and is one piece of curved metal that is held in place by small extensions that fit into the bottom liner(also SS) which you have to flex slightly to fit into place..  I could not tell if the starter was ceramic and there is no comment on the posters.  (the handbook was sealed in a bag.) The lid does have a thick seal at the bottom, but it did not fit flush. Did not see the Timberline but assume the materials are about the same.$1300 for this one.  Will get some pic for us.

 Thanks Okie, Nice  photos..I noticed wing nuts retaining the fire pot and the material it is mounted to looks like stainless then transitions to black coated metal.. In previous models this was a one piece

housing. I am curious as to the reason(s). It surely isn't cost..In a manufacturing world, one cent can sway a decision relative to materials, labour, warranty costs, serviceability, longevity and warranty costs.

 Thanks Okie, Nice  photos..I noticed wing nuts retaining the fire pot and the material it is mounted to looks like stainless then transitions to black coated metal.. In previous models this was a one piece

housing. I am curious as to the reason(s). It surely isn't cost..In a manufacturing world, one cent can sway a decision relative to materials, labour, warranty costs, serviceability, longevity and warranty costs.

Several things I do not understand:  As you said the housing for the fire pot is half SS. But also, there is a large SS sheet under the firepot assembly and it curves up on both sides make a double walled bottom as well as sides. It is screwed into place.  The exits for the downdraft exhaust are visible on either side of this sheet in the back.  I can see ash and debris building up under the bottom of the SS.  How would you get that out? By the way, I am convinced that the SS throughout the insides is about 18 gauge. You are correct, the firepot is held in by wing nuts. Fire pot is also light gauge IMO and has 8 holes.
Now I have these questions:
What keeps the heat from just going out the "downdraft" holes without going up into the chamber? Note they are below the drip pan level. Once those exits become the least point of resistance it seems to me that the air flow (or a lot of it)would just go that way without going up around the drip pan.
Why is there a thick heat seal at the bottom of the lid and not all the way around? (it also did not close well.)
Why is the deflector so flimsy? It gets the full blast from the pot.
One big positive, is that the cooking chamber is very high. Did not measure but looks to be over 10 inches.
Will be interesting to see some unbiased performance testing.  ???Happy Trails to you.

How does the Traeger Pro D2 575 look?

I’ve looked at them a couple times. Looks like the Pro looses the double side walls, the slide out and two height main grate, side shelf, and has a slightly different controller with fewer dedicated buttons and a 450 max temp vs 500. I think the new Pros look nice with the WiFire and taller elongated barrel and wider legs (that they’ve been adding on some models for a couple years). I’m actually considering buying one myself.