What should I keep?

What should you keep? The bikes obviously! ;)

If it absolutely has to be either/or then the Spesh IMO. It just looks so cool even as it sits & given you already have duplicate Treks makes it a no-brainer. Just make sure you actually need to keep only one!
Thanks for all the replies so far!! Although I'd love to keep both (I'll try to convince my wife she needs another bike since we have the same size, but with low expectations), I'm afraid even keeping one is pushing it, as my mother in-law is not super happy with me parking bikes in her house, even thought they have plenty of space. At home there is no chance with the kids bikes, the trailer, the tag along, the "follow me", eyc

So far it looks like the winner is the Rockhopper. I'll overhaul both, in case I get a last minute (bad) surprise on any of them, but it helps a lot to know which one is a keeper and which one is to flip when building a bike... Will post pictures when finished...
I would say the Trek all day normally but if you already have 2 then surely the Rockhopper needs to be kept
I'm happy to report that, against all expectations, I mentioned casually to my wife this morning that I would be selling the Trek bike soon, unless she wanted it, and she said YES! I guess it helped that I have the same bike with my parents in great condition and looks very classy, so she wants a bit of this...

Time to be creative with space in the storage room, sell one of the kids bikes that is anyway too small, and overhaul/bring the Rockhopper to my in-laws...

I'll convert the Trek to an urban cruiser with some very high rise bars I have. My wife loves classic bikes but even more an upright position... And she gets the ugly crankset, of course!