Kody, NiCads have always been and always will be rechargeable. I dont think anyone would be using NiCads or NiMHs if they were use once and throw away job.

NiCads are lighter then SLAs, but the SLAs can source a lot more current on peak then a NiCad and they can also take more physical abuse. The Nicads have a much better effeciency rate then SLAs and also are much lighter.