I like the looks and handling of the Sky over the Solstice and the MX5.

There's a guy that put 400hp on the Ecotec 2.4L (the one that comes in the Sky and Solstice) That should tell you that the internals are pretty stout in stock form.
I'll find the link. I think he put it in the Solstice.
here it is from Solstice forums.... http://www.solsticeforum.com/forum/s...ad.php?t=19280