Absolutely the best. I used to wrap the outside of my fabric pots with kitchen wrap plastic. (It works, don't get me wrong) but the aesthetics were terrible. . In came grassroots!!! Problem solved.
Keep in mind they 30s+ get heavy. Make a saucer with wheels! I used a 28 inch pontoon ballast. You can also look for hot water heater pans. Hard to find saucers this big