I have a Venge and I have an R5, and i honestly dont "feel" faster on one vs the other. If i am, it is probably a very miniscule amount. That said, I have wanted an aero bike - specifically a Venge - pretty much since the day those were released. Last year, i treated myself. Dura Ace Di2, CLX64, the works. I am super happy about the bike and get excited about riding it. To me, that is worth more than the marginal improvement in speed.
Also, aero bikes are pretty good all-rounders these days. My Venge clocks in at around 7.3kg in a size 56. So it isnt as if getting an aero bike will compromise your riding in any way. If the Scott makes your chamois all tingly, get the Scott. Just be sure that you wont have regret about the cabling
(You can probably find a bar + stem setup where the cabling is internal in the bar and then travels either inside the stem or is tucked away underneath it, emerging at the base of the stem near the steerer. This wont be fully invisible but it will look a lot neater.)