Gas buddy app is helpful to find lower cost alternatives, although most stations around me are within $0.40 of each other. I won’t go out of my way to get cheaper fuel but if I can plan my chore route around it I will go to the cheaper station.
I guess the only downfall to the older unit is end of life (Kubota supported) components will come up sooner.
With the newer if emissions are a concern that can be dealt with through the aftermarket.
Hearth.com is a forum with helpful users, much like this forum. They have a pellet stove section that’s fairly active. I peruse the wood burning section often.