97 Honda civic transmission fluid change?

I recently bought a 97 civic with just under 100 k on it. Car was beautiful kept with all service books. The transmission shifts perfectly but I can't find details of when/if it was last serviced. I hear that if you have a old transmission that may have never been serviced its best not to mess with a change as this can cause problems, is this true and also on those older boxes should I still use Honda new fluid or dexron as the book says either.

Use only genuine Honda A/T fluid and nothing else. Dexron is only to be used in an emergency when you have no other choice.

Fluid changes are important. Follow the recommendations in the owners manual. If given a choice use the cheaper of the two.