Thats nice to get them for free.
The NIB NiMH may have been old stock, since (non LSD) NiMH self discharge so fast they can actually kill themselves sitting on shelves for too long. Someone may have just stocked too many and let them sit for too long and had to write them off.
I'd buy a good charger like the MAHA C9000 (I just noticed it on sale at Thomas Distributing when I ordered some more eneloops so I e-mailed them to see if I can add one to my order as I've been waiting for a good price for a while) or Lacross that can test the batteries to see how good they are then you can group them together.

I just charged some ,I'll see how they work . They were in plain unmarked boxes , bulk packed if you will. They have Kodaks name on them. We are the home of Kodak , and this place breaks down their one use cameras,so I fugure they sent them these to get rid of for some reason also.

One guy at work has a 15 minute charger with a fan, mine is an over night one.