So I took my baby ('17 Siren Red Premier) to the dealer today because the MIL was on with the P0442 code plus I wanted some other items checked (infotainment issues, possible oil drip).
They gave me a fairly well-equipped silver '17 Malibu Hybrid as a loaner. During the 35 mile drive home from the dealer, I got to experience the ride quality and play with some of the functions a bit and I wanted to give a quick review. This is going to be mostly subjective so YMMV.
First - the steering, handling, ride, etc... all feel looser than Volt. I don't know if this is because the car is bigger or because it's a loaner that was driven hard in the 1,070 miles that are on it. The general feel in the cabin is similar to the Volt meaning you know where everything is and how to get to it. I did have to hunt for the USB ports (they are tucked up higher than the Volt and are not visible unless you really go looking for them).
Drive-wise it almost feels like driving the Volt in Hold/CS mode where the engine will rev at random moments unrelated to how fast you are going. This makes sense as the Voltec powertrain is being used. The Infotainment setup is similar but the energy screen is more simplified containing just the power flow section and a bar-graph thing showing what I believe your MPG is although to be honest, I have no idea how to interpret it. There is an extra 'Shop' icon on the infotainment unit which I believe connects to some sort of app store but I haven't played with it yet. I don't know why this couldn't be updated/added to the Volt infotainment system.
The radio in general sounds lousy even equipped with the Bose system. You'd think it would be comparable to the Volt but the sound in the Volt is much more dynamic with more resounding bass. The Malibu sound output is almost 'tinny' and yes I did set the EQ the same way I have it in the Volt. It also sounds lower at similar volume levels but I am sure that is due to the car being larger or maybe because the subwoofer is in the trunk vs. hatch area.
Regarding the power flow, basically I watched it during the whole drive and it tends to run mostly on battery + engine. The battery charge level held steady between 50-60% charge. It seems like regen was sufficient to bring the battery back to that state of charge when it dropped. Without a charging port, I don't know how you would get the battery to 100% though (if you even could).
I wouldn't mind having two-zone climate in the Volt. While the cabin in the Volt is smaller, my wife is the kind of person who sets to temp to 80 even in the summer which leads to some interesting conversations/discussions in my Volt

The front seats feel about the same as the Volt although I imagine they are a little bigger. I didn't sit in the rear but obviously there is more room back there.
I generally don't like the layout of the instrument cluster/gauges. The big kW gauge is kind of useless and uses up a lot of space. The digital portion of the dash provides useful information similar to what you find on the Volt (driving style, power usage, etc...) with a different layout due to the small size of the display. I wish you could combine items (e.g. digital speedometer and trip or driving style) but there is not enough room to do that.
Overall - it's a nice car and worthy of the $32k sticker price but I would never pick it over my Volt. The hybrid aspect was fine. On my 35 mile trip which is a mix of highway and local streets, I averaged about 44mpg which is not too bad. I do not like the loose feeling of the steering or the rattles present. Driving it just made me want to drive my Volt.
Just my two cents.
-DJ