The 50mm version should be slightly brighter in low light. With relatively low magnification like 3-9 and a quality scope like the Elite, it really shouldn't matter much either way.
BTW, why a 243 at 100 yards and less? Is it your only option? I'm genuinely curious. I've killed a bunch of woodchucks and at those ranges a 22 with CCI Stingers, or the like, is entirely adequate and a whole lot cheaper to shoot and quieter.
Still happily answering to the call-sign Peetza.
The problem, as you so eloquently put it, is choice.
He is no fool who gives what he can not keep to gain what he can not lose.
-Jim Eliott, paraphrasing Philip Henry.