This is very important if you want to climb free . Since then, many manufacturers have introduced new screws with about the same characteristics. Some of them are cheaper than the BD, which may not have been surpassed. On solid ice, I doubt that the extra length would make them significantly more solid. They take more time and energy to place.
Nobody is really sure whether long screws hold better than short.
But clearly, there is a point at which short becomes too short. Due to leverage, the outer-most ice plays the most crucial role in holding a fall, so there is also a point at which long becomes too long. Non-tubular screws are out, because of reduced holding power, difficulty to place or remove, or a combination of these factors. Ice hooks have a limited holding power but can be placed on thin ice. Hammer-in screws need two hands to be placed.