That's the thing, the boxster, Elise etc are not a completely different level of car. Honda delivers something unique that's hard to explain..on paper many cars are better than the little old Honda but there's a reason people sell their boxster s and go back to the Honda. It's unique/raw driver experience that not many cars can recreate and still cost Honda prices to run. Elise is probably the closest but they come with lotus built quality which is flaky at best.
I have driven VX220, S2000 and 986 Boxster S and yes the S2000 is all about the engine but the mid engine cars are a far better steer but the most important thing in a convertible is the engine and the S2000 comes out top by a country mile. The S2000 also looks the best and dare I say it more classy than a Boxster!
For me the S2000 is one of the best weekend cars in existence, it has one of the best 4 pot induction sound tracks ever, particularly improved if you remove the air box lid or fit a CAI, I personally drilled my air box lid in select locations and add some cold air ducting to get the noise benefit but whilst not increasing intake temps, so no drop in performance or heat soak. The later cars not sure what year it was but they put the sharpness back into the handling that early cars had but without them wanting to kill you as such they handle and drive nice even on the stock SHOWA suspension but even still the Ohlins are an absolute transformation and give the car a go-kart handling feel when turned up pretty high but still offering soe comfort, or just dial them back for better than oe ride quality.
For me the only weakness the S2000 has, steering though precise and direct is lacking in feel, I need to look into options to see if this can be remedied and the stock brake setup lets bite and is prone to fade but is easily fixed with better pads and fluid, these are minor issues really because the engine gives the car a real connection and rawness that for me gives the excitement of something like a Caterham nearly but none of the drawbacks of lack of comfort as its easy to drive several hundred mi,les in the S2000, plus they have aged so well.
An Elise though great is a very bare car, the lesser power models also feel somewhat gutless, they don't have that urgency of VTEC or noise, step up to an Exige however and those issues are no longer, but still lacking comfort, the newer Sport 3560 do look incredible however. VX220 just never did it for me, its not age well and the NA VX220 I remember finding it so boring to drive, the Turbo was however a rush. Porsches are incredible and the Boxster wins on the chassis being more exploitable at the limits as in its more friendly to slide around, but the early ones are slower than an S2000 as a 2001 Boxster S found out this weekend, they might have 10HP more but my guess is they are a bit heavier and until the 981 series Bioxster all the previous ones look very dated whereas S2000 still looks fresh, particular 04 onwards models.
The S2000 is just a very special car, the drivetrain is perfect for fun factor, lets never forget that gearbox, if it had Porsche steering and better brakes it would be perfect, the latter is possible, the steering needs investigation.
Other thing going for the S2000 they are becoming a rare sight these days as they do become weekend cars or part of collections and the last point, HONDA RELIABILITY and parts are relatively cheap.