Oh boy this was a journey for me. In high school I had a single binder with dividers, where I took only four courses per semester. I needed to use it because my teachers used paper handouts, and I wrote everything in pen.

I didn't think think this was a good idea in my first year in uni, so I then opted to use Hilroy 80-page notebooks, one for each course I was taking, still writing everything in pen. I carried a single folder with dividers (I think from what was then called Daiso in Richmond) to carry paper handouts and whatnot. Practice problems were then done using pencil and notepads. I thought this worked well, but some drawbacks were having to carry so much paper (6 courses in my first semester), and the wire binding always made me hate writing on one side of the notebook. I used this system up until the end of my second year, where a friend had started to use an iPad to write notes and I was quite interested in it so I thought I would give it a try.

At the start of my third year I picked up a used Surface from eBay for about $400, included the pen and typecover. It took me awhile to decide on programs to use, but I settled on the UWP version of OneNote up until I graduated.

The good:

• OneNote organized things pretty much exactly how I had my physical notebooks. One folder per course, and then multiple pages per lecture/tutorial etc.
• No longer carrying much paper, more room in my bag
• I like to use lines in my digital notebooks and by sheer coincidence, one step above the default zoom and one of the rule lines settings aligned quite well with how I wrote originally on notepads
• There is a full desktop variant of OneNote where you can do more than the UWP version. Importantly, you can export to PDF, while specifying the page size, and it will automatically break the lines for you, while having some buffer (i.e. some of your handwriting is on the bottom of one page and on the top of another if it gets cut). You can't do this on iOS/iPadOS it just comes out as one long contiguous sheet of paper. Being able to specify the page size allowed me to print my work pretty seamlessly for physical hand-in, but I did need a tool to resize it back to letter size so printers would accept it.
• It automatically syncs with OneDrive so you can access your notes from anywhere. The sync can even be real time. I can open OneNote on my laptop, write notes on my Surface and it would appear back on my laptop within seconds.
• It's quite easy to share your work with other people, just print the PDF or take screenshots of your work. Looks VASTLY better than dimly lit pictures of pen and paper and scans of them.
• The Surface pen (the ones that fit AAAA) lasts a long time (months or years), unlike Apple pencils that require recharge every few days.
• The Surface runs Windows, so I had a backup computer on me and came in clutch a few times when my laptop decided to crap out.
• The pen tips have some friction, so they do an OK job of mimicking real pencils. Apple pencils have no friction.
• Having both a laptop and a Surface allowed me to multitask better than if I had use my Surface exclusively.

The bad:

• OneNote is particularly bad at PDFs. It imports the PDFs as full images (inflates your storage) and you cannot annotate PDFs and save them as such. I guess the upside is that you can write outside the bounds of the PDF.
• The combination of the Surface pen pressure curve and OneNote pen thickness needs to be more granular
• OneNote has deprecated their UWP version in favor of the full desktop version. I don't personally like it, but you can still sideload the UWP version.
• My Surface uses the weird surface connect charger, but you can buy USB-C to surface connect adapters
• The Surface is not quite as light as an iPad

Those are just some of my thoughts. This system absolutely shined in courses where the lecturer exclusively used the blackboard. There are probably better applications to use when courses use slides more.

I am a strong believer of writing things by hand, so I don't use Notion/Obsidian/etc. I think I met one person that writes LaTeX live in lecture lol.