I just saw the interrail pass on happyrail.com and it is half the cost of the Swiss travel pass. I am going to be traveling over a 5 day period. Geneva airport to Interlaken, Interlaken to Lucerne, Lucerne to Rome. 2 nights each in Interlaken and Lucerne. No definite plans on itinerary in each city. Likely just day hiking trips, possibly pilatus in Lucerne. Do I really need the Swiss pass. What possible advantages I'm overlooking?

Are you European? The Interrail pass is for Europeans.

I am not! Thanks for the info!