I am also a fan of the B158 and B158B, not that I own either yet, but when funds allow the next light I will be purchasing is going to be the B158B.

I would like to see the B158 and B158B available with a single mode direct drive driver. Even better, but probably not possible due to the design, would be a dual switch set up with tail switch for on/off and side switch for modes, one of those modes being direct drive.