Well Taffy, if you don't do it "now", you probably never will. The longer you contemplate the negatives, the less likely you are to jump in.
As I recall, the rear window glass was a glue issue, and Asbo, Brian & co will know more about what followed. I assume there was a recall, and I don't think production was complete at that time so the later Maxes should have been corrected anyway. I might be remembering wrong but didn't the rear glass get through bolts on the hinges?
The glue on the rear windows could weaken, causing the windows to come lose from the brackets that held them in place. Whilst the original design was more streamlined, it had the drawback that the 'butterfly' windows were constantly under pressure and thus when the adhesive gave way, the windows would fly off.
Mine did this when the car was parked and thankfully, the window landed back in the aperture, without damaging the bodywork (a bit of luck). Other owners were not as lucky and they gave way whilst the car was in use... flying glass projectile! or did as my Max did, throwing the glass into the air, only for it to land edge down damaging the bodywork.
I had mine fitted with the new glass (which has holes in the glass to affix it to the the brackets) but I know some owners decided to risk it, preferring the lack of the four bolt covers on the butterfly glass; during Brian's ownership, he decided against having the change made to ARO8 MMC.
I believe most, if not all, the cars were built when the issue became known, so most would have be a post-production fix, if the owner opted for it.
