I found this at http://www.nature.com/news/the-exoplanet-next-door-1.11605
Even when launched by one of the most powerful rockets on Earth, boosted by a gravitational slingshot around Jupiter, and further accelerated by a radioisotope thruster, that probe would take about 28,000 years to reach α Centauri. Quoting British author Douglas Adams, McNutt quips: “Space is big. Really big.”
Is this still the fastest we can get right now?