I successfully have been using the Bro-Tek rear wheel spacers for several years with no issues. My sloped hill-side ground makes my Kubota BX-25 much safer!
Yes, I use the spacers with foamed tires, lots of hours, on my second set of foamed front tires, ready for a second set of foamed rear tires, and not problems Still a very good addition to my BX24.
Are foamed tires as heavy a ones with rim guard (beet juice) ?
NO wheel spacers on the front end with 4x4. No reversing front wheel rims. Bearings can not take the loads. Tractor will be more stable - setting in the garage with a broken front end.