Gentelmen,
I just put rimguard in my 2210 rears. I've seen rims replaced becasue of CaCL and didn't want to deal with the hassle 5-15 years from now. It took some time on the phone finding a dealer, I ended up taking the tires and driving 30 miles to get them filled at a small tire shop.
I asked a local Kubota dealer why he didn't carry Rimguard and he said you couldn't mix it with other products, so coupled with the low demand and high price, they still use CaCL about 90% of the time.
Price was $3 gallon, we broke the seals and dumped in about 10 gallons per tire. It's pretty thick reddish stuff, so it very well could be the beet juice product gpod was talking about earlier. I think RimGuard is headquartered in Michigan as well, so it makes sense.
Hope this info helps a little.