Wheel chock suggestions??

[92 5 oh]

fathers day is around the corner, my dad has tandem axle camper and I was looking at getting him some decent chocks. Currently he has some dinky plast things for a 32' camper.
Does anyone have any experience with the kind that go between the wheels and expand?
Specifically I was looking at these
http://www.northerntool.com/shop/tools/product_200442243_200442243
Thoughts?

Thanks!

 

[94xcab4x4]

I have always seen these at the camp grounds and was wondering about them too. But i think my walmart cheapes are good enough. Personally by the time the jacks are down front and back i don't think my camper would move any were. Sorry this post is a little late. ALso did you buy them for him and how does he like them and how much did you get them for the price that was in the link you posted or something esle?