I got myself a bunch of Chinese pens last month and have been trying out a few of them since.
My 'test-drives' have included writing out two A4-sized sheets continuously and filling up another A4 sheet with random line patterns including a checkerboard. Surprisingly, I see a pattern in some of the pens.
Of my four Jinhaos put to the test, the blue celluloid Century has performed nearly flawlessly. Straight out of the box, without even a flush required. It sometimes doesn't write after I've stopped using it for a while but once it starts, it keeps going effortlessly. The X450, X750 and 159 have been a massive disappointment; I've flushed the pens, taken apart the nibs and feeds and carefully cleaned the feeds with dishwashing soap and a toothbrush (as recommended on a website) but the problems continue. And then I just thought of chucking the 159's Jinhao cartridge converter and replacing it from another standard converter. Knock on wood, but that seems to have done the trick for the 159, which now can't wait to get out of my pocket and on to the paper... incredible! When I pulled out the Jinhao converter, I saw that even on inverting it, the ink didn't drop down and was 'stuck' to the top, for the want of a better term. I suspected a breathing problem or whatever (could even be a small plastic sphere in there that's the culprit).
No idea if this fix would make the X450, X750 and Kaigelu 323 usable but there's one final remedy that I now can try ere trashing them.
I have three Picassos and these are by far the most reliable of my Chinese pens. The Dukes are still in the box and might yet perform well but the Picassos are hard to complain about. They're not my sort in that I like pens that are moderate to big-sized. The Picassos are all slim and dainty but never once have any shown the slightest hint of skipping or are there any other problems.
Has anyone here had a similar experience?