I'm very happy with my 2015 Felt Z85.
It's not the lightest bike - about 19-21 lbs. But I wanted a bike that feels a bit more stable on down hills, and this bike feels great.
The 105 is so dialed in - shifting is amazing.
The bike is all stock except for the seat. I really don't want to change anything.
...but that's not to say that I wouldn't want another bike. I like variety.