There is no reason these cars can’t be daily drivers, they were designed to be (they aren’t Ferrari’s)
Of course, that is if you can have a little two seater convertable as a daily car.
As mentioned, buy the best one you can afford. Remember in their “day” they were expensive sports cars. They still are, sort of. If you can find one with maint records do it, if you can find one with all the big stuff done, do it (you will pay a bit of premium) or be prepared to spend some $$ on any variety of things. Regarding S vs standard, I don’t think it really matters, but an S is an S...
I absolutely contend, that if you get a good one, they cannot be beat bang for the buck. Period. If you get a bad one, they can be expensive frustrating things until you get them sorted and they become a “good one”. But then, that rule applies to just about any car out there these days. I don’t think these cars are tons more $$$ to maintain than most, particularly in the super fun, sports car world.