I'd stay under 350lbs no matter what. Anyone who was climbing up there would need a special ladder. Idid ladder certifications for LADOT and followed OSHA specs, I have never seen a 350lb rated ladder in an RV.
"I travel not to go anywhere, but to go. I travel for travel's sake. The great affair is to go". R. L. Stevenson
David Bishop
2002 Winnebago Adventurer 32V
2009 GMC Canyon
Roadmaster 5000
BrakeBuddy Classic II