had a 300d perkins it ran great currently own a 200d kubota runs fine in the summer but starts hard and runs very cold all winter
I have a 300D with the Kubota and I love it. Make sure to get it load banked when you get it. The RPM control can be really useful.
Personally, I'd go with the Kubota. I own two of them and I've been servicing quite a few of them in generators. A good engine.
Tom