Jouplast paving slab pedastals

[jackpot]

I want to raise a grass area as it holds water in the winter for a few days and either pave or gravel. I was originally thinking of a plastics grid system topped with aggregate and then decorative gravel, But now considering the pedestal systems. Both would allow the water to drain underneath.

Im assuming I will need some sort of aggregate down on the grass area to support the pedestals. Could i just put the aggregate on top of the grass and compact?

Does anyone have experience with these?
Trying to weight up how much materials, how much work involved etc.

Thanks