The MR2 Spyder uses a 1.8 l, 1ZZ-FE motor, lower compression & output VS the 2ZZ-FE in the Elise. So I'm not so sure how easy the fit and tuning would be. IF Toyota is doing some work for the 2ZZ-FE Elise it'll be something to keep a eye on.
I'm not sure why they say it will work with the Elise. They're not even the same motor. The Spyder has a 1ZZ. On top of that, I have seen pricing for it around 6,800 Euro. I don' know the conversion off the top of my head, but that's one expensive Turbo for not a lot of performance. There are significantly better Turbo kits for much less money available for the Spyder. If somebody wanted to swap out with a 1ZZ and install a turbo, Hass and Stafford Fabrications make the best kits available right now. They are getting around 215 rwhp on about 8-9 psi. A stock 1ZZ put about 120 HP to the wheels. These are complete kits with everything you need and go for only around $3000-4000.