We just got back from our maiden voyage and also experienced the "rotten egg smell". On our last day we started smelling a sulfur smell that we thought was coming from our kitchen sink.
After we got home we determined the smell was actually coming from the steps which is right by the kitchen sink. Turns out both our coach batteries boiled dry, once the step was off it was clear this smell is the batteries.
We are calling the dealer today, and my husband thinks it is possible they are being overcharged.
2006 Itasca Sunova 30B