The 1s have been on sale lately, but 500Gb - 1Tb is a little small for my personal tastes. If I were you, I'd do a hybrid setup: grab a 500Gb for your boot drive and a conventional drive of at least 2-3Tb for data storage.
The thing is I really don't store that much and when I finish a game I will generally uninstall it. Of course, there is the argument that AAA games are getting larger in size so a 1TB might soon not be enough.
For reference my current (from a four+ year old build) HD is only 500 GB and I've never come across a situation where I simply couldn't install the handful of games I play concurrently and that's even with trash like WoW taking up space (and I only play that like two months a year... probably not at in the future, though, since I think the new expansion is awful).
[For further reference I don't download much in the way of movies, tv shows, music, etc.]