Well barbarian will win the race to CS because he can hop I think Vigor is faster than inc speed. How about they team together! Vigor + inc speed is crazy fast :xmas22:
Frenzy actually is the most impressive- a lvl 20 Frenzy fully charged gives +171% FRW, which is absurdly fast and often results (for me) comedic crashing into walls and things. Of course you have to hit something to get going, but it can be very impressive. L20 Frenzy (171%) + Hawkmail/Blinkbat's (+10%) + Treads of Cthon (+30%) + Irathra's set (+20%) + L20 Increased Speed (43%) means winning lots of footraces. I did exactly this for fun a while ago and other players thought I was somehow using a hack. It's that fast.