I just completed a drop bar conversion on my 2008 Bike Friday Tikit. Original had flat bars and a single 8-sp twist shifter. I'm not a fan of flat bars, much prefer bars that allow multiple hand positions and play nicely with brifters. I've played with mustache and bullhorn bars, but keep coming back to drop bars, so that's what goes on most (if not all) of my builds.

I went with Sora 8-sp brifters (although I only need the rear to shift, single chainring) on Nitto B-135 randonneur bars. Love these bars; they're narrow on the tops and wide at the drops. Lizard Skins DSP tape to complete the outfit.

Yes, the drop bars do make the fold bulkier, but for me, the improvement in comfort far outweighs folded size. Still easy enough to throw in the back of my vehicle or on public transport.