I have a very hard time using cheap, generic fluids and greases of any kind. Your "average" system might hold 15-20 gallons of oil. Last pail of Hytran we purchased was about $60, or $12/gallon. An extra $75-$100 to change hydraulic oil should not be a problem for anyone, including someone who runs a fleet. Hydraulic/transmission oil lasts a minimum of 500 hrs, some machines the change interval is as high as 5000 hrs. If you (I don't mean "you" personally) are one of those guys that dumps all the fluids once a year regardless of hours or condition, there might be a little bit of merit to using generic stuff, but I personally wouldn't. Leaks need to be fixed, clean machines run cooler and have fluid that stays cleaner anyway.