I've had two now, a pre facelift 02 plate and a post facelift 04 plate both in silverstone (technically all UK cars are AP1, just pre/post facelift, as every S2000 nerd likes to tell people).
Loved my first one, did about 20k miles in it in a year or so, sold it due to wife having some back problems which meant she couldn't go in it anymore.
Second one bought as a bit of an impulse buy about 5 years after the first thinking she'd be ok in it now as her back was a lot better, nope sadly not
Hardly did any miles in that one, didn't even have it a year before getting rid (know one of the guys at Torque GT who sold it for me
https://torque-gt.co.uk/car/honda-s2000-2/).
One of the previous chaps had put one of the Monsoon replacement mohair hoods on it, was pristine when I had it still and was a lot nicer than the stock vinyl.
Actually just remembered sold my first one to them as well!
Never really gelled with the second one, the handling felt rather floaty even with the alignment all ok, plus I got old in the time between them and whilst it's the best feeling manual box I've ever driven found it annoying pootling around, in traffic etc, missed my auto
Pushing on it was great though, and can't beat roof down fun.
Controversially I always used to say they would be awesome with a sequential/paddle type box.
There's not a huge amount I'd do to one unless you're craving big power with a charger of some sort, just make sure the suspension isn't all seized up, get the alignment sorted and just drive it