I have a silhouette SD (baby cameo) and an eclips, among others.
To be honest, it would be a tough choice. The eclips (which I love beyond all my machines) can cut thicker material than the cameo, but if you want it for card making, that isn't such a big deal. The cameo does intricate cuts and print&cut can't be beat. Not to mention it can be gotten more cheaply than the eclips.
To be honest, since I've upgraded to the designer version of silhouette studio (the basic version comes free with it and you can download it from their website to play with it) I use my sil exclusively for print&cut. It is just such an effortless thing with silhouette studio, and to be honest, I struggle to do the same things in scal.
I would suggest you check out Jins blog at:
http://underacherrytree.blogspot.com/
She has cutter reviews for the silhouette SD (no longer available, its being replaced by the silhouette portrait but basically the same machine) and the cameo, plus tutorials for silhouette studio. SVGCUTS.com has the best price currently for the upgrade.