I bought a Wingsung 699 recently from AliExpress because I wanted to try out a vacuum filler. Ink leaks from around the nib whenever I cap it, leading to ink getting on the grip. When I write, blobs of ink sometimes burp out onto the page. Is this typical for this brand? I have another no name Wingsung (I think it's actually a knockoff of the Hongdian dark forest) that has no issues.
Hmm right - you would think that the shut off valve should keep any expanding air out of the nib. between that and the leaking, maybe you just have a defective pen with some issue in the sealing of the shut-off valve?