I have use Honda Power Steering fluid in a wide variety of vehicles such as GM, Ford, Toyota, Nissan and Mazda. Even helped slowdown a leak in an old '88 Grand Marquis that my dad owned before he passed away.
Honda Power Steering fluid is all that I use in my 1980 Firebird FORMULA P/S unit...Have for years!
I also thought there was P/S noise in my daughters car so, I used Honda Power Steering fluid in her '06 Mazda3 when she bought it in 2009. Only to discover the unit is electric P/S. I did a turkey baster method and added the Honda Power Steering fluid to her unit. Everything is FINE... I have recently done the unit again but this time with IMV ATF. P/S unit is smooth!
I have some sticky/hard steering in my wifes Lexus and used Honda Power Steering fluid it this unit which calls for DEXRON. The Honda Power Steering fluid hasn't helped but, it didn't hurt either. Needs more attention I guess. No leaks or noises, just stiff!
Honda Power Steering fluid works fine and won't hurt anything that I am aware of. The Honda Power Steering fluid worked well in curing the morning sickness in many GM units and can certainly be used as a topoff in just about any vehicles P/S unit, if you have some Honda Power Steering fluid remaining.