Preparing for an overseas trip, I'm finding holes in my m4/3 lens line-up, since I'm only bringing m4/3 and can't fall back on my DSLR lenses. Currently my widest lens is Panny 20/1.7 (not counting kit lens). Is there an affordable, wide-angle prime (around 16mm FF equivalent) that is worth having? Doesn't need to be particularly fast. TIA.