Steam Cleaner For Hardwood

Looking for a good option to clean prefinished engineered hardwood floors that have a Polyurethane finish. This is a large space, and we like the results from a Bissell (1544A) steam mop, but every manufacturer cautions against using a steam mop (can damage the floor and/or void warranty)? What is your experience? If using the steam mop on the lowest setting with quick passes, has anyone here ever had issues with the hardwood getting damaged.

Another option is to use something like a Bissell Steamwave (23157) with a spray attachment or even an Oreck Orbiter and spray down some Bona hardwood flooring cleaner needed. I just like the convenience of the steamer.