Had an Elise and would have loved an Exige. I still can't help but lust after another.
I'm not a Porsche fan by any stretch but your choices look like a weekend weapon v an everyday super car. I would lean towards the Porsche although I can't believe I'm saying it.

 

Just re-read the thread - you want a tool for the weekend so it has to be the Lotus

 

Porsche is sexy!

And I dont like Porsche's!