Interesting results.
I have to read a lot of PDFs for my courses right now of 50+ pages.
I find reading on a phone too difficult. Even when I let the PDF Reader reflow the document, it's still hard on my eyes.
A laptop is OK but not great. Big screen, but it's kind of far away on my lap.
My Kindle is nice for reading, but it doesn't show preformatted full-page PDFs well.
I'm interested in trying out a tablet or iPad. We'll see.
Thanks for the responses everyone.