The D4 is a 2.0 diesel I think, 0-62 in 7.4 seconds and I get an average indicated mpg of about 55, that’s with a fair chunk of stop start driving in town.
It’s not huge in the back but easy big enough for bikes with the seats down. I’m not sure if it has mounts but the xc models come with roof bars.
For me, it’s close to the perfect car, nice to be in, not too big/small, drives pretty well but not at the expense of comfort, quite quick but still economical. I sat in a golf and didn’t even bother driving it, just felt like a depressing place to be. I had a 118d BMW for a while too, it was nice enough but I prefer the Volvo.