Hover Ball for Slider Exercises

I'm always looking to improvise products toward usage in gymnastics drills.

Today while at Rite Aid, I happened to notice a product called "Hover Ball".

I could not take it out of the package, but it appeared to be a foamy half sphere glued onto a furniture slider. 

When I got home, I looked it up.

Personally, I think it's a pretty lame toy.  Especially for that price.  And I don't think it's probably that hard to tip over. 

However, as a slider for conditioning, I think it's comparable to my friend's product, the Xpodz.

Hover Balls ae $9.99 at Rite Aid.  I'm tempted to get a couple even though we now have plenty of Xpodz foot sliders at my gym; and I have a pair of Xpodz as well as an ab slider.

I'm wondering if I get 4 of them, they could serve as a base for a small block for some creative block pushes....