flooring methods/ prices

About to have jarrah floor installed. A new house concrete floor. Direct stick or plank on ply?
Need to know if the extra is really worth it (plank on ply) as there is 190m2 of floor and the cost is already high.
As long as the slab is done well would I really notice the difference.
What is a rough price people have paid for complete floor installed prices including beading everything(minus timber costs). Also the complete cost of ply installed. Just want to see what people are paying in the south west WA.