Short version

Arrived on time and for ~$20, this is a great low-cost alternative I can permanently keep in my backpack to take notes with when I travel. My $129 Apple Pencil stays at home on short trips!

Summary

At the end of the day, it’s great for 17 bucks, you can’t complain for everyday annotation type of tasks. What you’re paying $129 for is a more refined experience - the Apple Pencil just works - you pick it up, use it, then dock it. You never need to worry about managing its state (if it’s on/off and whether it has sufficient charge). After using my Apple Pencil for 3 months I realized I’d taken this aspect of it for granted - it elegantly solves handling a wireless device to the point where it doesn’t become “one more accessory to manage” - “it works like magic” - it’s the kind of integration you get by being part of an [[Apple ecosystem]]. Is this one aspect worth 102 more bucks - by itself, no. The other advantages that are useful (eg. for drawing) need to come into play. While it clearly might be a bit overpriced for a young child, it is the kind of experience that really made me think twice and hesitate as to whether my niece would really find it useful to learn to draw with a knockoff Apple Pencil on her dad’s iPadPro.

pros

it's $17 ($20 w 2 extra nibs which fit real Apple Pencil)
it works fine for handwriting, general markup of PDFs (don't notice any difference!)
doesn't require bluetooth pairing
tips interchangeable w real Apple Pencil tips (possible source for replacement tips?)
magnetically clips
USB-C
single charge lasts a very long time! (you don’t need to charge it daily (or even weekly if you are a light user!))

cons

it lacks a refined "always on" experience
- have to manage "on" state (Apple Pencil is "always on" because it assumes you will dock it when done (which charges it)) (ingenuity in #design)
- have to keep it charged (lasts long anyways & turns off on its own after 5 min idle) (Apple Pencil seems "always charged" because it is docked most of the time)
too easy to toggle on/off at "eraser end" (this is my biggest gripe & something I think would frustrate a child!)
magnetic clip not strong
magnetic mount not centered
potentially requires separate USB-C charging cable (though you’re really not likely to have to charge both devices at the same time...)