Looking for a Large-Screen E-Reader for PDFs (Textbooks)

I have a Kindle Paperwhite, but it’s terrible for reading PDFs—especially textbooks—due to the small screen and sluggish zooming. I’m looking for a dedicated reading device with:

• At least a 10” screen (larger preferred)
• Native PDF support (no conversion needed)
• Color would be nice (for diagrams) but not a must
• No annotation needed—just reading
• Not an iPad—I find full-fledged tablets too distracting

Any recommendations? If you own a device like this, what’s your experience with it?