I've tried them and do use them in the PG for comps.
I have laid them on the back side of the firepot, have used some wielded wire to make a shelf to the side of the fire pot and used them there, have made a wielded wire extension from the little hand made shelve and used them at the level of the heat shield.
My experience with them on the PG is that they burn real quick, I have started wrapping them with foil to help with the ashes blowing around and to slow the burn time.
My next experiment,when I get a wild hair, will be to cut them down in size and lay them in the ash tray.
They make 3 different sizes, so you have a lot of options to choose from.As of the present time I use the large Hickory ones and lay them over the heat shield on the very front part, they are wrapped on 5 sides with foil. I really can't tell a lot of difference when it come to flavor, but I think it does help a little with color.
If you try them, please update us on your findings, thanks in advance!