Nope you don't need the disk after install, it's a Steam game, the disk only helps you install the game faster. I wonder if you have to put the disk in the PC at all, I've not tried entering the activation code into Steam before running the disk.
I can't really comment about the Augmented edition, I felt a bit like it was going to give me an advantage that I didn't want, thats not the reason I didn't get it though, it just wasn't in the online shops and I really wanted to get this game. I'd say get the Limited edition, I haven't used any of the stuff that you get from it. The unlockers could be seen as a cheat, but when you get to a decent hacking level they don't really give you any advantage other than breaking into place faster (Useful when there are patrolling guards etc) but hacking gets you more money, exp etc so it's always worth hacking.
I don't regret not getting the Augmented Edition, I have enough trouble carrying around the stuff in the game as it is, but then it does open up more options.
I can't really comment about the Augmented edition, I felt a bit like it was going to give me an advantage that I didn't want, thats not the reason I didn't get it though, it just wasn't in the online shops and I really wanted to get this game. I'd say get the Limited edition, I haven't used any of the stuff that you get from it. The unlockers could be seen as a cheat, but when you get to a decent hacking level they don't really give you any advantage other than breaking into place faster (Useful when there are patrolling guards etc) but hacking gets you more money, exp etc so it's always worth hacking.
I don't regret not getting the Augmented Edition, I have enough trouble carrying around the stuff in the game as it is, but then it does open up more options.