Unfortunately not an option for me. Too tall. Can’t fit in the 986s either. Really it is down to a Z4 or 987 for me.
Ah well, just wanted to toss out my experience!
Btw I’m 6’5", maybe it’s because I’m skinny, I made it work.
My 6’2” son was fine with the top down in my Fiat 124. (Italian Miata)
I’m 6’5" as well, but my knees were up against the dash and wheel and my head rubbing against the top. This was a '24, maybe earlier generations were a bit more accommodating.
We really need to get together a pickup basketball team.
I have a 987 (a 2008 Cayman S) and quite like it, but note that we ONLY drive it for fun so has under 50k miles in all those years. Maintenance is expensive, but very routine and I’ve barely done more than manage the expected bits (gas, oil, brakes, tires, a cracked windshield once).
It’s fun and very direct and neutral given the weight balance and engine location, but it does for sure have higher limits than our previous sports car (a 1996 BMW M3). Under any kind of normal driving the Cayman will feel responsive, safe, high revving, and fun, but it will also feel pretty much glued to the pavement. You’ve got to get into serious curves, surface undulations, and speed to load up the Gs before it starts to feel spine-tingling and a little risky.
But then it’s all relative.
I once had a very unplanned “exciting” moment in our Honda Accord when the tires suddenly lost grip on a rainy side street during my morning commute and the car did a few spins down the street before it settled going the same direction in which I’d started. That car handled well for a family sedan of the era, but it rode on narrow rubber and had low limits. Much more butthole clenching than fun was involved 
Fwiw the Miata I bought was from a guy that had bought it to replace his Boxster.
To be fair, it was the unholy Australian SP version of the Miata, with a bolted on turbo and 160kW. That was fun to drive.
Boxster 987 S thoughts. I have a 01 Miata for 8yr and had a 03 Boxster S for 6yrs until recently selling.
The Good
At or very near the bottom of its depreciation curve. I sold my 986 boxster for $6000 more than I paid for it. So as for depreciation, there was zero.
Its an excellent sports car and GT car. What I mean is its fun ripping around corners, but can also drive hours without beating you to death. Yes, around town the Miata is often more fun because the Porsche only becomes fun at a bit higher speeds, but long road trips in a Miata is really not fun. The shriek of the flat-6 when pushed is something the Miata cannot approach. Also in the Boxster you have much more luggage space.
Ergonomically perfect. OK different people will judge this different, but in the Boxster all the sight lines, mirror placement, and control placement was just spot on. My 6’5" son fits fine in the Boxster, not so much so in the Miata.
The specialness: Again subjective, but the Porsche makes everything a bit of an occasion, from opening/closing the door to starting to whatever. Other drivers ever give you more room/respect/following distance relative when you are in a Miata (Rodney Dangerfield of cars?).
The Bad
Porsche tax is real. Parts are 2-3x what you expect. You can save on that by finding OE equivalent, ie part of Audi or Bosche labeled instead of Porsche
I had zero issues that stranded me. I did have 3 repairs over ~6yrs
-lost one headlight unit. Like other modernish headlight, that was expensive.
-half-shaft seal started leaking.
-ignition switch started getting finicky. This is a known part problem. Relatively easy and inexpesive to DIY repair.
The IMS bearing failure issue is also real. if it fails, you write off the engine. You did not specify year, so I would research if you are impacted and if this car already had a replacement. If it hasn’t had a replacement, plan it as part of buy-in.
Actually, not for a 986/987. Those are older Boxsters, at the bottom of depreciation. They generally cost less than a new Miata.
You could get an older Miata cheaper than a 986/987 S, but even if you turbo or supercharge it the Boxster will have advantage unless you really go superheavy boost (and then reliability is crap). The only way to get reliable power is to engine swap to a 6 or 8, but then your cost just jumped up to 986/987 range to get it done well.
Thanks. That was a lot of good feedback, I appreciate you taking the time to write it up.
It is a 2006, so, from what I have gleaned, it is still a possibility, though a much lower chance than previous iterations.