Most commercial LEDs use 460-470nm blue due to cost savings. The most efficient photosynthetic response is at 445nm and 420nm (which is even more expensive unles you use T5 actinic or dual actinic bulbs). Note that the aquarium market always leads the indoor growing market and they are using 445-455nm.

If you are on a budget, use 460-470nm. If you want the best possible go 445nm.