Vallejo paints are great and their starters don't cheap out on the size of the pot. You do want Citadel's washes though. The only good wash Vallejo makes is their rust. With that said, color matching vallejo to Citadel doesn't always work out great when following along with the videos. If you are new, you are best off following the videos exactly for the first few projects. Then you can deviate a bit with the cheaper (and better) Vallejo paints. Though you can buy black, white, and german grey.
You best bet is to make the list of paints you need from the videos, Soroastro is real good about listing them, and going to a local game store and buying just what you need for what you are currently painting. Slowly over time you will have a big collection of paints, paints that all get used which you can't always say about some of those bottles in the big paint sets.
One thing to look for is a sale. Some stores may have a 10-20% off or a buy 5 get one free type deal. You can take advantage of that. And yes, painting hobby is expensive.......