Range Ball Storage Life

[Patch]

Several years ago, my company was involved in a couple of golf course clean up jobs. During the clean up we collected a few thousand range, and regular balls. I have several hundreds left over. They have been in storage for the past 9+ years. The storage room was subjected to winter, and summer temps, as it was not climate controlled. I am thinking of donating all of them to a local course for use on their driving range. 

Here's my question. Is there a shelf/storage life for these balls? I hit some of them earlier this year, and they seemed ok, but I am not a long ball hitter either. 

[iacas]

I don't know that the course would look a gift horse in the mouth. Range balls aren't exactly super expensive materials prone to lots of damage for moderate temperature changes.

[cristphoto]

Everything I've read says 5 years is normal life and beyond that performance starts to fade.