Single-length iron sets are a good option for beginners and high handicappers. Using one iron setup helps to minimize learning time since there are fewer setups to learn.
When you hit single-length irons, you set the ball at a specific location to get the correct launch angle and trajectory.
Yes, TaylorMade makes single golf irons. TaylorMade irons typically utilize a hollow construction which provides a low center of gravbity and a muscle back shape. With a forged face, a higher launch, faster ball speeds can be achieved.
There is no set rule about all irons being the same length however, for beginners and high handicap golfers, having irons of all the same length can make learning and hitting easier.
Flex refers to how much the shaft of the golf club bends during the swing. There are generally five ratings for flex: extra stiff, stiff, regular, senior, and ladies. Your optimal flex will vary based on your technique and driver distance.