I was able to upgrade to a S-WORKS SL3 frame set which leaves me with a SL Pro frame and fork. I'm thinking of selling it but then again, I could hang on to it as a back up or even pick up some ebay parts and build another bike, maybe use a compact crank for hilly courses/rides.

Anyone keep a spare frame around to use in case of an accidental breakage?

A second purpose hilly and/or century bike sounds like a good idea to me. Wanna sell it for cheap?

Id keep it and build up another bike.

Also, pics of said bikes?

Crappy cell phone pic of the SL3;

If you don't have a backup already, buy new components for the new frame and hang on to the old one.

single speed

Of course you hang on to it. How could anyone go through life with just one bike?

I keep many spare frames and bikes - though none are for accidental breakage.

Uber cool single speed?

sell it if you need the cash, but otherwise, nothing wrong with a spare bike or few.

the old n+1 idea. I've got all three road frames I've used since getting into the sport. they're all worth more to me at this point in sentimental value than what they'd command on the open market.

Either sell it now or commit for the long haul. Having a second ride is never a bad thing.

Use the Force!

(Sorry, I couldn't resist the obvious bad joke...)