I have driven a couple...they are heavier, more flexible (especially a unit-body), cold in the winter, noisy (even top-up), usually cost more to insure for full coverage, they tend to leak. Way too many compromises.
Everything you said is true, but once you own one you'll be hooked.
The Dart is my second convertible and when the weathers nice, morning or evening drives are awesome.
And if you have kids (I have 3 under 10) they will love it too.
I don't know what other american made convertibles are like, but the Dart has been well engineered considering it is from 1967, it's not just a coupe with the roof cut off.
