Nico Nico Nii!~
The new tins only sort of make it easier to build a competitive play worthy deck. They come with the promo in the window of the tin and 4 booster packs from different sets, as well as a mini-figurine in most cases. Not exactly the most reliable way to get the cards you want, but a pretty good way to build up your general collection. That and I personally think opening booster packs is a lot of fun, even if you don't pull what you want. I only recommend buying the tins if you're also going to be trying to collect the cards at the same time as being a competitive player. Otherwise, buy individuals of cards you want on, say eBay or Trollandtoad.com.