So Im assuming you can get it back and spend it on something else?
I think thats normal unlock tokens, not permanent.
As for Ghost, it's rather decent. Suppressor is recommended along with an SMG. I've got a fair amount of triple kills today after I tried it out - it makes flanking so easy. People really radar watch in this game, so when you keep off the radar then you'll easily do well.
"My name is Spartan Jay, the greatest MW3 player of all time. Because I am on your team, this team will win" ~ Spartan Jay
Ghost is only worth using on shotgun/smg rushing classes. You stand still for a second and you appear on the radar. Apparently the ability to counter ONE killstreak makes Ghost overpowered so it was nerfed into oblivion.
I thought a similar thing and it really didn't do all that much to improve my game. I find it helps just as often as it doesn't.
For example: when you see someone run through a door and get shot, do you immediately follow? If the answer is yes, you are wrong lol. So if you do the right thing and don't immediately follow and wait to see if the enemy will run through said door, you literally have to run in circles for Ghost to not have you show up if the enemy has a UAV up. If you stop to wait, you show. If you take a knee or go prone, you show.
If you never stop moving then it works great, as long as you are willing to run a silencer. However, it is hard to never stop moving, especially if you play objective based modes and have to capture dom points, hardpoints, or headquarters.