Dot-5 ok?

Thanks for all the input - great site! I've had no issues with DOT5, but if I'm supposed to change either kind of fluid every few years, I wonder if it's worth the extra cost to keep using DOT5. Sounds like performance and reliability are about the same, so other than being easier on paint when spilled, I'm not sure I see enough advantages to justify the extra cost. Guess my next question is if I want to change back, can I just drain the DOT5 and replace with DOT3/4, or does the system need some kind of flush?