For those on the market for something the size of a standard sheet of paper whats recommended? Side loading PDFs and the size I mentioned are the main requirements. I'd prefer not to jail-brake but I have and I can.
There's also the Fujitsu Quaderno gen 3 as well - half the weight but can't do epub or mobi.
Like the Sony DPT readers, the Quaderno is would be great product ... however,
1. there is no customer service in the EU/US markets. Something broke? Bin it. 2. the devices are quite fragile, with poor longevity. 3. the closed source software does not support modern systems such as Apple's M4 Macbook series.
Disclaimer:
If you're reading and annotating a lot of full-sized PDFs, then bigger is better. But for just taking notes, drawing diagrams, etc, I found a smaller device was a lot more portable and convenient.