I used to own a 156 GTA saloon a while back and it was fantastic, it was my daily driver for 4.5 years and never put a foot wrong. I really wish now I had not sold it!
I found it did the motorway cruise very well and would average low 30s mpg on a long run, normal driving for me was more like 21-22mpg but I did not have a very long commute and it would constantly egg me on to press the loud pedal anyway!
The boot is a reasonable size for a saloon but if its practicality you need then a GTA sportwagon would be the way to go, but these are pretty scarce. Back seat space wise it’s probably not much different as the 147, those huge front seats block most of the forward visibility for back seat passengers plus leg room is a bit tight, but they do get their own door on a 156 so access is much improved, it also has three 3 point belts in the back but the middle seat is raised up and quite firm.
The turning circle is worse than the coupe, yes it is that bad!
What should be a 3 point turn will be more like 5. But on the plus side steering is very sharp on the road. I had a Q2 diff fitted to mine which transformed the handling/power delivery, and really is a must for any GTA now. As it’s more a question of when not if the diff will decide to spit its innards through the gearbox casing!
I found the traction control system very dim-witted especially in the winter and found the car to drive much better (with aQ2 fitted) with it switched off, the down side of which was chewing through front tyres alarmingly quickly!
Then there’s THAT V6 which along with the coupe 20v are in my opinion the two best sounding (reasonably affordable) engine notes out there!