What is better- a V-shape or a hex crimping?


The crimping can be reliable only if you carefully matched the inner diameter of the core and inner diameter of the lug barrel.
Hex connection has positive mechanical strength and ensures a bigger area for electrical contact between the core and the lug. If you have chosen the sizes correctly, the connection is almost leak-proof, does not damage separate cores, it looks good as repeats the shapes of the cable shape.
V-shape crimping is useful when the inner diameter of the lug barrel is bigger than the diameter of the core. Moreover, it is better to crimp solid wire with a V-shape die.
V-shape dies can be called universal as they can crimp lugs in almost all type and size, using the tools ПМУ-120 or ПМУ-240 made by KBT.