The vast majority of trails have no official width limit, the steel bridges are only 72" wide so that should not be an issue.
For those that want to hit 50" trails they can just branch off take that route while bigger machines go around, the scenery is awesome everywhere. The wildlife viewing opportunities are better for the P500 trails but the wife and I ran into wildlife everywhere we went. The leaves will be turning in the mountains this time too, should be awesome photo opportunities.
About the trails, these are Nothing like at RRB most is dry desert like environment, replace the mud and ruts with rocks, lots and lots of bowling ball size rocks. These trails are overall very easy but descending switchbacks from 10,000 feet up with 600 foot dropoff can be as intimidating as it is breathtaking. Never in the 3 weeks the wife and I rode there ever come close to tipping over or feel unsafe on the trail system. Most familiar with RRB would consider 80% of these trails gravel roads, I will just put that up front. Most trails are not challenging in any way, there are bathrooms along the trails and marked on the maps too. (Women especially will appreciate that).
My only concern now is very high narrow bridges 
