I don't know where you guys find these incredibly useless tyres. Certianly my two local indy tyre firms would never sell anything like that. I guess they are happy to see their customers return to them for more tyres rather than laying in a hospital bed or worse!
At present I have continentals all round on my 147. When I bought it it had Conti's on the back and something-else on the front, but as I do prefer the same tyres all round on my car (balances the handling don't you know) I matched up the new fronts I put on with those on the rear.
Now I don't drive like a mad-sarse-hod but I do enjoy the handling capabilities of my Alfas, yet I have never got anywhere near the limit AFAIK.
T'was the same on the 156 (GoodYear E-Agles) and the 146 (Pirrelli P6000 or something).
Now I am sure that there WERE differences between these different brands and also that on a test day at Brands (

) you would be able to measure the difference between them, but I put it to you that on the road, provided it is an established, well known make, it will make bugler all difference.
They all cost around £60 to £80 a throw (depending on size), which these days is just the cost of a fillup, so why bother with real cheapos?
P