That allegro looks nice. That seems like pretty much a direct comparison to the FX, having an aluminum frame. I guess Sora components are rather low end road stuff, but I've personally never tried them, so can't comment. I've ridden 105, and Tiagra, but never Sora. The aforementioned two are just wonderful.

With the allegro MSRP, you seem to be in 7.3 FX territory, though. It has deore rear d., which is pretty good mountain stuff, or so I read. I can say that the deore on my 7.3, and the one on my Felt, for that matter, shift very well.

As was mentioned before, you'll have to ride them. Once you do, you'll know. I wouldn't give up on the Trek before riding it.

To further muddle things, that PDX looks great to me. Nice price too. Good luck