Your fuel tank would have to be really filthy for B5 to clog up your filters. B5 is 95% petrodiesel, so not much biodiesel is in it. Even with higher concentrations of biodiesel, if your fuel lines start to weep, they would have done that anyway sooner or later on petrodiesel which dissolves rubber too, though probably somewhat slower. There was someone on this board who had a regular fuel hose sitting in a jar of B100 for 6 months with no apparent harm so I definitely wouldn't worry about B5 dissolving rubber. I used B5 before for almost a year in all of my cars and even tried one tank of B100 and I never had any issues with filters plugging up or rubber dissolving.

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2004 VW Jetta TDI (manual)

Past MB's: '96 E300D, '83 240D, '82 300D, '87 300D, '87 420SEL