Depends what you want from it mate. Will you be using it every day as your main mode of transport? If so, I guess the Elise would start to grate after a while - most peeps I know that had/have one have also had a company funded crate to trundle about in and use their Elises as weekend toys.
That being said I'd definately have one over a Mk2 MX5 as I had a 2001 1.8i (not an S though) for 3 years and compared to a Mk1 it felt fat, flabby and generally quite boring to drive which is why we sold it, we got absolutely zero buzz out of the experience and ended up using our Polo diesel nearly all the time instead.
Bear in mind insurance for the Elise can be eye-watering.
Why not look at a later Mk1 MX5 instead? If you must have a Mk2, at least go for an S-spec car with the slippy diff and make sure it has proper wheels (not aftermarket ones that eff up the suspension geometry).
Oh yeah, and get a move on, the summer's nearly finished...oh hang on, my missus says its never actually started
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