I like this Tamron 17-50mm lens as a step up from my Canon kit lens but it doesn' have vibration compensation?

Its a 2.8 lens which I really like and its only like 300 dollars but the one with VC is 500 dollars but with that kind of money I would buy a better lens because 17-50mm isnt so great. I do a lot of video so I really think I would need the VC. How could it be a step up from the kit lens if the kit lens is one third the price and has IS? It go great reviews though. Maybe the should get the Sigma 17-70mm OS 2.8-4.5 for 450 dollars. What do you think?