Kubota was considerable cheaper on the RTV900, higher on the 3940 and slightly cheaper on the ZD326P. This is compared to the company that has my home policy (Germania). I have Kubota Insurance on the RTV900 and the ZD326P.
Be aware if you buy the Kubota insurance when you buy the equipment and pay off early they will cancel your insurance when you pay it off. And then call and offer to insure it for you. At least that is what happened on my RTV900, I was without insurance for about a month and didn't know it.