Coming back to the original questions:
I think you'll find a 2015 V8 a great experience and depreciation on early models should not be bad at all - especially of you pick a good spec and color. They are paddle shift but not double clutch auto so if you want a manual type experience better stick with manual.
I nearly pulled the trigger on a 2015 V6 but decided I couldn't not get a V8, so without wanting to spend much more than low $30K's, I decided on a used 2014 V8 that I can have fun modifying (wife insisted on a convertible).
Dont forget to join the MCA to get access to X-plan pricing - that will get you $2-3K off list on a 2015. Some dealers are also offering $2-3K off a 2015 if you place an order with them.