I just ended up buying an extra battery for my can. . .
For me, since I'm always laying line for wreck diving, the enclosed head design of both the Halcyon and Dive Rite (MR11) 10W HID is much more rugged IMO, than any of the test tube designs of the Salvo HID Lights and can take a lot of abuse (i.g. inadvertently banging into ship's ladders, stanchions and pipes etc. while laying/reeling-in penetration line). I also thrashed a test tube head type once before as well, when I got rolled by a rogue wave in the Surf Zone of a Beach Dive. . .