Researched from the sources below. This is not a hands-on road test.
Start with the experience
The Mazda MX-5 is a two-seat, rear-drive roadster; the Toyota GR86 is a rear-drive coupé with a boxer engine. Those layouts suggest different ownership experiences before a single acceleration number enters the conversation.
Our question is personal: what part of driving do you enjoy? An open roof, a manual change, a compact footprint or carrying friends can matter more than the winning figure on a specification sheet.
Make the compromise visible
Try your actual luggage in the boot. Sit in the car with the roof up. Test the seat position, visibility and how easily you get in and out. A weekend car should still fit the person using it.
Write down the journeys the car must do and those another transport option could cover. This separates a delightful compromise from a frustrating daily mismatch.
Choose with a real drive
A researched specification is useful for a shortlist. It cannot tell you how a particular seat supports you or how a used car has been maintained. Book a legal, unhurried drive and compare impressions immediately afterwards.
Carioo has not road-tested these cars. This is an invitation to ask a better question: how much car do you need to enjoy the journey?