I've seen published weights that indicate the FSA Gossamer cranks are lighter than the SLK's.
We have the Gossamers. I would second the point about FSA cranks not being the most reliable. We trashed the BB's in 800 miles.
However, they're working nicely with the replacement ceramic bearings. Now if we could get the Captain's crank to stop creaking we'd be in business.
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You could fall off a cliff and die.
You could get lost and die.
You could hit a tree and die.
OR YOU COULD STAY HOME AND FALL OFF THE COUCH AND DIE.