Here’s a visual comparison. From the top… Pilot Metropolitan, Jinhao X750 Shimmering Sands, Jinhao 159, and Lamy Safari.
Both the Jinhao’s are quite heavy (twice as heavy?) but even with my small hands I’ve enjoyed using them for drawing. Both come with medium nibs installed and I’ve found they’re really smooth… haven’t had one skip since I’ve inked them up… De Atramentis Document Black is waterproof and the pens have handled it well. If you find you’d like a finer or broader nib it’s possible to exchange the nibs and put in a Goulet Nib. Both are #6 and from what I can see are easily exchangeable. As you can see, the #6 nib is larger than the nib on the Pilot Metropolitan. I’m going to play with these a while before I decide.
I know I’m not giving you much time to mull this over… offer ends at midnight.