Fastest in hyper, or fastest in system?
In system: Sprints and ETAs (old CP) are about the fastest sublight ships you can find, with the sith starfighter (current CP) just behind. All of those are int eh same speed range as an a-wing in system.
Hyper: Fleur is right that a 510 is about the best there is. But there are other ships with similar hyperspeed ratings that are more economical, like the yt-2000.
the YT-510 is about the best combo of both, though, for ships that are typically commercially available. I'd say the sprint is just behind it, but also well worth the investment, as it is cheaper, has a slower hyper, better sublight speed, and the med room, and better cargo and NPC capacity.
neitehr allows you to carry a vehicle, though, do if the 'Derra rules' for ships ont eh ground become a real thing galaxy wide... both will be limited.