Uniflex shafts

[Rackster]

Can somebody explain these. I have found out they are in between a regular flex and stiff flex. An owner of a golf shop was trying to sell me a set of Nike NDS irons, with the Uniflex shaft. He said the shaft adapted to your swing speed? Is this true?

I currenty have stiff shafts in my irons, but I find the feel limited in the longer irons, and sometime I lose my iron shots with a high push to the right. Will a uniflex shaft help me.

Thanks