I suppose this could also go onto a rules board, but as it's more of a "why" question I'm posting it here for now; feel free to move it if appropriate.
Basically: the main benefit of both targeting computers and arm-mounted actuator enhancement systems is to provide a -1 to-hit bonus to any eligible weapons linked to them. (Targeting computers also allow for aimed shots at moving targets, which AES doesn't.) Yet targeting computers add 25% to the BV cost of any such weapons while the AES increases it by a whole 50 percent. What was the reasoning behind that?
(While the AES also boosts non-weapon-using physical attacks with that arm, that's already figured into BV elsewhere and in any event would come at the cost of not actually using those weapons as well in the same turn. So that alone can't easily be the reason.)
