I've got new formula brakes, and I'm replacing the hoses with Goodridge hoses. I've got an Avid bleed kit, which came with a small bottle of dot 5.1 brake fluid. The brakes were initially filled with dot 4.
My questions are -
Is it worth swapping the dot 4 for the dot 5.1? Will there be a performance benefit?
If I do swap, how do I flush the old dot 4 out of the system?
How careful do I have be about making sure the two fluids don't mix?

