It's pretty poor, or am I missing something?
I was looking for Twains Innocent's Abroad with original illustrations. My normal source is Internet Archives. I'd download a PDF, fix it a little for eink screen, and that would be it. I wanted to try some alternatives for variety, and I stumbled on wikisource page of it, and it was really promising on first look.
Good formatting, illustrations in decent resolution, formatted, proofread, pdf, epub and mobi options available for download. Second look was already pretty bad. All downloaded files are per chapter only, and illustrations aren't as high quality as available when viewing the page in web browser via links. So, if I wanted to make a serviceable ebook out of this, I'd have to download each chapter separately, combine them, and possibly also do something with images as well. Oh, and I'd also need to remove disclamer at the end of each chapter
edit.
Source that they use was usable, though. 300mb djuv. OCR'ed and formatted. Initial problem was finding a link for the source itself. With wikisource, there's a million links that end up nowhere, and exactly one single link that downloads full .djuv for you. Also, it turned out that source for the source, was sourced from archive.org, so I went full circle for something that I would do anyway.