has anyone tried these ?
Price is right.
The Skisaver Flex is well-made -- all steel -- and the box weighs 26.5 lbs, so this is not a light-duty product. This product, with solid wheels, has been used worldwide since 2015 and are more durable than air-filled tires. This product is adjustable, so one set of Skisaver Flex ski wheels will fit all of your skis and your friends skis when they load on your trailer, and your future sleds' skis. (This second generation Skisaver Flex is adjustable to fit all skis, compared to the old styles that are fixed and only fit certain brands and certain skis.)
The cheap knockoffs posted earlier in this thread broke and had wheels that didn't last. The manufacturers have been forced to take their products off the market due to patent infringement as they were exact copies of the original Skisaver.
Skisaver Flex has patents issued and patents pending on the original Skisaver (launched 2015) and the adjustable Skisaver Flex. The company is challenging other companies' more recent patents on the grounds that you can't patent a product that is already on the market ("Prior Art").
So compare the features and buy the product you think is best.