In my fairly large collection of pens, my Pilot/Nishiki Vanishing Point stands out as number one for travel and number two overall. This fountain pen has traveled with me around and around the world. Designed with a retractable nib and o-rings to keep the ink inside, this is the only fountain pen I've felt safe flying with.
The weight of the Vanishing Point is just lovely. The clip is in a funny place but not in the way at all, and kinda charming. The fine nib flows ink well, and I routinely use this pen as my instrument for writing with blue ink.
If I owned only one fountain pen the Vanishing Point would probably be it. The $150ish price tag, however, makes it harder to swallow for folks who just want to write with a fountain pen.
This Pilot Capless is reportedly the same pen with an alloy instead of a gold nib. It also appears to cost 1/3rd less! Having used many pens with stainless and alloy nibs, you will find it slightly stiffer than gold but if you don't have one to compare to, you probably won't notice the difference. This is approaching audiophile territory.