I'm not stalking you I promise.
It all depends on the application.
Remember though, you could put multiple 14V battery packs in series to get 28V, 42V etc. So just because your charger is only rated for 14V doesn't mean you are limited to that in terms of battery packs. Sure, it'd be a pain to charge, but that's a sacrifice you'd make.
Most microcontrollers that we'd use run off of anywhere from 2-5V DC. It's the other things in the circuit that would require more. Like if you had DC motors that ran off of 12V or even 24V. That's one of the times you'd need to have a battery pack rated that high.
So, it depends on what you want to use it for. I think you'd be fine with the cheaper one. You can build some big robots on 12V power supplies. (I mean think about cars!)