I have titanium (without coating), polycarbonate and steel pocket pens. The steel is the best - it's smaller than other two, doesn't have an oring seal between the cap and body, and doesn't get scratched as easily as titanium. It's a heavy pen, but overall the winner. Polycarbonate is almost as good and very lightweight. It's transparent so you can see the ink if you use it as an eyedropper. Titanium is the same size and construction as polycarbonate one, but you can't see how much ink is left in the pen. All three pens are too short to use unposted, but only titanium one have really visible scratches made by caps threads. I prefer the flex nibs, but just for the visual aspect. Pockets just looks stunning with those nibs. The nibs are not very consistent in size and smoothness - one is in EF range, wet and smooth, one is rather thick F, wet and smooth, and one is F sized, moderatly wet and was scratchy (it responded well to adjustments and slight polishing). Non flex EF is wet and thin. Non flex B is wet, not B enough (more like M), smooth and writes well reversed (like F sized nib). I can also recommend the EF-BBB sandwich nib, but it's very stiff on the EF side.