"Knipex Cobras: The 6" Is My Ideal Goldilocks Tool!
This is just a lightning quick video featuring the differences between the 6 inch Knipex and the 5 inch Knipex. I've found that between the 4, 5, 6 and 7 the 6 seems to cover almost all ground (for me) and it's not as bulky and large as the 7 but covers more than the 4 and the 5.