My first post too. I believe the Muses is similar to the Mars device except there's no sdcard and has more built-in memory
https://youtu.be/7gn1KSkbKR0 is a comparison video.
I haven't messed with the hand-writing a lot, I bought mine because the kobo aura one was being depreciated. As an ereader, I love it. I've side loaded brave browser and moon reader on there and it's great for reading. The lighting is more even than my aura one. I use moon reader to connect to my synology running cops with my personal library and import books with no issues. The usb-c cable it came with is junk so if you can't connect to your computer, try a different cable. The boyue launcher is junk too, haven't found one I really like with e-ink, but at least you can load launchers.
I'd say it's the perfect ereading device but if you have a mars it's pretty much the same thing without expandable memory and usb-c.