This is an excellent club for grooving your swing. After just a few practice sessions, I was completely confident with the driver. The head is 460 cc's and is stainless steel. The hinge can be adjusted with an allen wrench for sensitivity. The handle is a rubber wrap which a bit too firm for me but is standard in size. You can actually hit with this club but your mechanics have to be 'perfect'.

You learn the importance of tempo, swing plane and proper mechanics. The accompanying video is helpful in the appropriate use of the driver. The swing tips video is also worthwhile.

PROS
Teaches the proper swing plane for those with a smooth tempo
Adjustable resistance to hinge at a lower threshold

CONS
Heavier weight than the conventional driver which may change your perception of feel
High price

There are lower priced alternatives; however, at a fraction of the cost (Refiner Driver - has a single hinge but the action is exactly the same.

ReFiner 460cc Hinged Driver, Right Handed, Mens

SKLZ Rick Smith Refiner Driver - Hinged Training Club

VERDICT

It is a great training aid but there are other choices on the market. 5 stars