Picked up the silver 2003 NB (112k, one owner) in late July and the 1997 NA (142k) a month ago.
While driving the NB, enjoying all the top-end power, I was convinced that it had the NA beat. But after a while I noticed the ergonomic issues. Shifting into 2nd or 4th would cause my elbow to hit the rear cupholder lid, popping it open almost every time. To fit in the driver's seat I had to remove my wallet and place it in the cupholder each time otherwise the intrusive door arm rest would squeeze against me.
None of these minor flaws bugged me at all until the NA showed up a few weeks later. Both cars were handpicked and meticulously pored over by me, checked head to tail for major defects and driven extensively up and down the track at the dealer auctions. I immediately noticed that the NA was less stiff compared to the NB but also less prone to understeer. Both cars had sticky new summer tires. NA's ride quality was slightly better as well.
The NB's power steering feels sportier and heavier while the NA's feels a bit loose and overboosted. A popular thing to do, of course, is remove the PS hardware from the NA. I drove Christine's '96 R a couple years ago and indeed, power steering is unnecessary on the lighter NA.
The NA also has significantly more interior width thanks to a center stack and console design that's low and out of the way. Head room is greater due to a seat cushion that's lower though slightly less comfortable on the tail bone. The NA's shifter has longer throws but action is smoother, lighter, and more enjoyable to engage, slipping easily through all five gears.
NB's Nardi wheel was perfectly sized and shaped while the NA's wheel was hideous, typical of air bag steering wheels from the 90s.
Additionally, the deeper trunk in the NA is easier to fit my laptop bag and file box in.
In the end, I decided the NA was the better everyday car even though the NB was the stronger performer with a stiffer chassis.
I went back and forth over whether to keep the NA for myself but owning two convertibles is slightly absurd, plus the Saab has four seats and a massive trunk. Then while I was out of town my phone blew up with offers and both cars sold quickly. The decision was made for me.
Suddenly, I went from two Miatas to none at all.