Karma Tennis
Legend
I have never found one that I really liked. Have you?
I imagine you have seen this thread ...
The bottle cap solution seems interesting.
I only suggested the customisation on the off chance you didn't know about it. I am not a fan of extended racquets mainly because I feel I have better control and more comfort with shorter length racquets. I think in a lot of instances a 26.75 inch racquet would be preferable to a 27 inch one.
It's a pity no racquet manufacturer can develop a technology to make the racquet handle USER customisable in terms of length and size simply by manipulating the handle itself.