i excpect Apollo will also still play loud enough in 30 years.
The grade of humidity and temperature affect the sound of every speaker but the treatment is for lifetime when you avoid too much direct sunlight on the cones. Even when a percentage of the oil drys out the flexibility of the cone will last and the laquers i use are violin- varnishes which are proven for hundreds of years.
Since the Apollo are dipoles from 100Hz on they won`t behave completely different like other speakers in your room, additional they offer the possibility to easy- tune the basses to the belongings of your room, so they are less placement- critical than passive speaker- designs. At RMAF the small hotel- room was not ideal for them but even there the sound was ok. and regarding your room i recommend to start at the place where the speakers you use now are placed, this should also work for Apollo. Regarding fine- tuning there are many possibilities and you get full support from my side, i have done this many times with good success for the Prometheus and i know the speakers are flexible enough to allow this in a wide range to the belongings of your room and taste, also Bill and Tony have experiences with this speakers and can help to bring them to "the point".
Regards
Robert Bastani