Ah, is the dealership far away? If not, you can call ahead and have them get the car ready in front for you to swing by and drive. You’d only have to test the 40 TFSI since I reckon there’s not much difference between the 45 TFSI you have now and the newer version. I will say though that if you hadn’t experienced either, it would be easier to pick the 40 TFSI and be satisfied. But in your case, I can’t imagine you’d like going from a 45 TFSI to a 40 TFSI. You’re going to feel like you downgraded.

When I was debating between the two, it came down to a difference of about $2k so it was easier to jump to the 45 TFSI. For a 10% difference in price though, that’s about $5k which is a bit more significant.

Tough choice in your position. You can try and negotiate the 45 TFSI down a bit which might help.