I have a set of ribs that I built 25 years ago. They have been stored in my attic and have been kept dry. They have been exposed to the high and low temps of the attic.
Do you guys think these would be ok to use or should I trash these and build new ones?

Test one: https://www.youtube.com/watch?v=VxMY19Gya1Y

If the wood breaks before the glue joints fail they should be fine.

I know how you feel. My plans-built bird was begun with the tail feathers and the ribs in 1990. 20 years later it was finally completed and started flying regularly. Any thoughts of performing stressful maneuvers are tempered by the realization that many of those epoxy joints are 27 years old! So far, after eight years of flying, the only failures have been in the areas which hold the wing tanks. The weight of the tanks wiggling around and expanding/contracting eventually broke a few members loose and they had to be re-glued. Needless to say I fly conservatively.