Miatas are definitely fun to drive, but I could not take myself seriously when I had a chance to ride in/drive one.
They have the 'small car' appearance, meaning they look like a caricature of a car. In reality S13's and S14's are not much bigger, but they have great proportions so they look like a 'normal' size car.
It is not a bad thing, it just all comes down to one's personal priorities.
P.S.
Are Miatas prone to rolling over? It seems that a lot of people end up flipping them.