nice! yellowstone has a fleet of e350's with the mattrack systems they use for snow coaches.
i would already have a set of tracks if i had 40k of extra cash laying around. hell even used ones from mattracks are 38k. cheapest ive seen them was in the 12-15k range, but every set ive seen for sale in that range was across the country and with shipping, it took it back up past being affordable. so i gave up having some for the van and started looking for our wagon. ive emailed every manf. ive seen asking for load ratings on their utv tracks, not one has returned any of my mails