The scenario on borrowing the whole $85k on a Raptor at sub-3% rates, paying $1500/month and investing it becomes problematic if we have a 30-40% correction and that $85k that could have paid cash for the Raptor becomes $50k in an S&P 500 index fund, you still owe $80k+ on the Raptor that's now worth $60k due to declining asset value, and you are still paying $1,500/month.
My strategy would be to pay the $85k cash for the Raptor, take that $1500/month you'd be giving the bank to pay down your principal/interest and dollar cost average into an S&P 500 or some other good index fund for the next many, many years. Rinse and repeat. You're never caught with your pants down owing debt on a depreciating asset.
Until you can do the above, follow a Dave Ramsey type deal and drive a beater until your debt is gone (besides mortgage maybe), you've built a cash/investment stockpile and then start buying the fancy toys (i.e. Raptors, etc.).
But then again, we live in an instant gratification and FOMO society, so do whatever you want as long as you can sleep at night.