What are you throwing right now and how far are you throwing it?
There's no single best answer for everyone.
When I started, I drove with a Shark, as it was about all I could handle. So depending on how new you are, a distance driver could be a terrible idea. Without knowing how far you throw what, I'll throw out a few, from slowest to fastest.
Innova Teebird or Eagle, Discraft Stalker or Cyclone, Lat 64 River
Lat 64 Saint
If you can throw a Buzzz straight and far, try a Leopard. If you can nail that, try one of the others. If you can throw those over 300, Try a Saint. If you can throw the Saint straight and far, then you're ready for the ultra-long distance drivers and you'll just have to throw a lot of them to figure out which ones work for you.