Don't know about the "sales hype", I can only go with actual experience with the device, which is that it works as advertised.
I do agree that a jump pack may be a more versatile device for RG, the dual battery set-up for a very occasional discharge is like swatting a fly with a sledgehammer.
I'll PM you about the device, you are misunderstanding how it senses voltage discharge.....boring details for the rest of the readers of this thread!
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