There is to consider the already short life of the Blast bulb will be shortened even more with rechargeable. From my experience, the Rage bulb show'd no problem in being fed with rechargeable.
With two different Blasts, I timed 15 and 20 hours of life with Ni-MH, and about the double with alkalines. The Rage bulb lasts 40 hours on either Ni-MH or alkalines.
Hope this helps
Anthony