My 156 TS was a nimble beast but my tractor GT is not!! All 3 of my spiders will run rings around it and I suspect GTVs will be even better
Odd. I have never driven or been driven in a 156. I have been in a Brera 2.4 JTDm (it was good, very good). I own a Tractored GT, a 916 Twin Spark Spider and a Ferrari F355 as well as the shagged A4
The Spider and F355 were made in the same year and when pootling along they feel quite similar (other than the Spider creaks like an old house), however for performance and sound the Spider won't go near it.
Now the GT, my GT will walk all over my Spider and back again, handling, speed but not comfort, in fact the F355 is probably the best ride out of all. However put the F355 and the GT on a small twisty road and it would (in my hands) keep pretty much with my F355 I reckon.
I have no proof of this of course, I can't drive them both at the same time and have never (and won't) done time trials but the GT feels properly sorted whereas the Spider is lovely to drive but performance and handling are not a patch. There are obvious differences in age and mileage, the Spider is by and far the highest with about 105k, the GT 80k and the Ferrari 24k.
To the OP, my best advice is drive one of each. Thing is all being secondhand one 159 might behave entirely different to another, see the comments from me and others in this thread. Age, owner and past servicing perhaps??