Too bad these are not really that decent. They are basically a cosmetically modified Chibi. There are nicer, inexpensive pens available. My go to for experimenting is the Nemosine Singularity. It's a nice size, is available in a clear demonstrator, is easily converted to eye dropper, and takes a standard #6 nib, so you can get a wide variety of nibs to use with them.
dementiaI've tried about five different JinHao's. They are fine, but I tend to like slightly lighter pens and demonstrators, so my go tos are Nemosine if I want to swap nibs, and the Pilot Petit 1 if I don't. But for nicer pens, I love my Pilot Custom 823, Platinum 3776, Lamy 2000 and Vanishing Point.
papadageI just bought another Nemosine pen because of this thread lol. The first one I got we're planning to hack it with a leonardt G nib. This one is as itself since I like how the Nemosine demonstrator writes. I've never tried Petit. My hands are huge but I think the Petit is really cute.
dementiaFor crappy little pens, they write decently, and they post to a good length, with a decent section. And even when I don't write with one for weeks, it still starts every time.
dementiaMy hands are larger, and I have several of the Pilot Petit pens that I have converted to eye dropper style. Thankfully, none of my Petit pens have developed cracks or stripped out along the threads, unlike my J. Herbin pens. My Chibi pens from Jetpens.com have been great as eye dropper conversions as well. I love pen hacks - I will have to try the Nemosine demonstrator hack, but with a Leonardt Extra Fine Principal Nib. The G nib might be too wet for me.