Tarmac Sport as its a great bike, the SL4 has specific carbon layup respective to frame size as different size and weight of riders require different levels of compliance and stiffness.
Bianchi try so hard to be Italian exotica however the bikes are still made in the far east, yet assembled in Italy so they can make this claim.
I personally have a hard time telling them all apart because of the icky bluey greeny celeste the majority come in and it is for this reason you rarely see really individual ones. The Bianchi's which really turn my head are usually in some really unlikely colour which makes the bike look cool but probably got the owner kicked out of the Bianchi Cult.
Someone on this forum has a really deep blue one which looks good... but celeste