All cars generally depreciate 15-20% in their first year, so the depreciation amount is going to be proportionate to the initial value of the vehicle.
A $200 000 Aston Martin is going to depreciate upwards of $40 000 in it's first year, leaving it worth a "meagre" $160 000. Whereas the BMW M3, at $70 000 retail, will lose maybe $14 000, giving it a year 2 value of $56 000.
We're looking at some vehicles right now in the 2-4 year old range, with ~20 000 - 30 000 miles on them. Originally, as new vehicles, they were valued anywhere between $70 000 and $110 000. I'd never pay that because I don't want to lose so much money....but the depreciation follows somewhat of an inverted law of dimishing returns, where the losses plateau and value is there.
The XKR starts around $100 000 cdn. A 2 year old one can be nabbed for around $50-60K, with maybe 15 000 miles.
A BMW M5 starts around the same...maybe $80k. 2 year old models are out for close to half that.
But people who buy new cars don't care about the depreciation, otherwise they wouldn't be buying new. And people spending $200 000+ on a car are likely ones who want the car and dont' care one bit about what it's going to be worth when they buy the brand new model year 12 months later.
AM's hold their values pretty well after the 3 year mark...as do most vehicles as long as the mileage isn't being racked up through the sky.
In terms of the aesthetic of the XKR, I find it so close to the Aston that it could easily be mistaken for one.