Heavy,sturdy definitely will keep the umbrella in place. Just one little thing to make this product a five out of five star product. Put a lip or handle on the other side of the wheels. Otherwise you have to pry your hands under the base and lift to make use of the wheels on the other side. like putting a handle on a door. Makes sense. 

Pros: heavy,sturdy, does the job
Cons: Hard to move around. Not customer friendly