Id rather have full tanks as there is less room for explosive fumes(gases) to ignite,We prefer to do maintanance on our a/c with full tanks,Ive actually seen a ringer on a cattle station put out a cigi in a freshly opened 44 of fuel(we ran like hell from this d@#$%head) but he was right nothing happened.
Cap Fathom I think the 310s and 402bs have a complex fuel system.How ever 402cs nave a very simple system,no auxs just lh and rh tanks,I heard heaps of freshly 310 indorsed pilot trying to understand tere few systems