If I were in the 85-90k market. I'd be looking hard at a certified used RS7, E63S, or GLE63S. Audi and mercedes offer fantastic CPO warranties. But everyone wants what they want and I encourage everyone to buy what makes them happy! You only live once and it's just money! Best of luck!
RS7s are even less than that. C7 RS7s are in the $60s now. C7.5 RS7 is in the $70s-90s depending on if you opt for the RS7 Performance spec.
We just knocked out this RS7 the other day. It’s a phenomenal daily. Seats 4 comfortably, AWD, nice ride with air suspension, averages over 20mpg, and 0-60 in sub 4 seconds. Phenomenal machine.