My spruce tops started out a bit stiff & improved with age. No significant change in the voice though, just better quality. Some major splitting with the tenor guitar but playing community halls when it's 40 below will do that.
The cedar top was almost unusable to start with due to some strange overtones etc. but sounds lovely now. No splitting but it hasn't experienced the same climate changes. Still not the greatest for strumming but lovely for finger picking. Woody, louder & mellow.
For my money, spruce is the safest. It will eventually sound better than new. With cedar your just not sure how it's going to turn out.
I thought I responded to your last thread.
Now does someone want to tell Sorcha about yellow cedar?