I sell a turf tractor that used a Racor 2 mic fuel/water seperator. They came out with a service bulletin and switched to a 7 mic because they plugged up to quick and customers were complaining of low power. The 2 mic actually filtered the dye out of the fuel. If using a low micron filter, I'd say you'd better carry a spare with you. As long as you get clean fuel, there shouldn't be any problems . Just my . 02.
Jim
If you check out the Racor website, they have a pdf file discussing micron ratings and filter applications. Their recommendation (and Bosch's according to the pdf) is that if you have to use a 5 micron filter or finer, you should install a 10 micron prefilter ahead of it. 10 micron catches the big stuff, 5 micron deals with the small stuff, end result is you still end up with clean fuel and it takes a lot longer for both filters to clog up to the point where they require replacement, than it would if you were running a single 5 micron or smaller.