Had a hands-on experience today, a tad dissapointed. The unibody doesn't really feel solid to be honest. I'm currently using the S7 edge, not a fanboy of any manufacturer but I think LG's selling point for the G5 would be for the modular concept. Not for the looks or usability.
In-hand feel, not liking it. I used the Gflex 2, G4 and v10 all of them were solid phones with great in-hand comfort (especially the v10).
UI is great though, less clunky. Really like the wide angle rear facing camera, but I think I'm spoilt by S7's low light and quick focus capability.
Just my two cents worth.