The original Palace on wheels used to be on metre gauge (track width is one metre). The new Palace on Wheels is a broad gauge train (track-width over 5 ft). Broad gauge trains are wider, faster nad more comfortable. Heritage on wheels is on metre gauge. Palace on wheels has private bathrooms attached to your cabin. I am not sure if heritage has any showers but toilets are shared. Palace on wheels departs from Delhi, while the Heritage departs from Jaipur.

I think for some one who has not been on Palace on Wheels heritage would be a good expereicne. But it would be a let down for someone who has been on Palce on Wheels.

If you plan on visiting Mumbai, I recommend the Deccan Odyssey.

The deccan Odyssey