If your asking if you can get by with uneven ground, I would say yes I bought one of these last year, and I did pretty much like the video shows I just walked around and picked up sticks and rocks, and I had no problems, and my ground was uneven by at least two inches.

One thing I would do is when your looking for rocks I would take off your shoes and walk around bare foot. It's better find them with your bare feet before you set the pool up, then after.