Was looking at these when I had the Impreza. Don't suppose you know the before/after DBs? Idea was to make sure it was quiet enough to get into the 88db days at croft (though I don't think that would ever happen!).
I owned a Mk1 MX5 for about 4 months when my old one broke and got bored of that quickly (Missed the power of the turbo). What about a FIed MX5? Plenty around. Supercharger for no lag, low end power, Turbo for silly numbers :D . Just make sure it has a LSD. Totally different experience to the MR2, ...