I use Sumatra to read a lot of scanned books from archive.org and the 3.1.2 version had a lot of hesitations between pages of hi-resolution scans. For the past month I’ve been using daylies and they perform significantly better! I look forward to the next production release so that I can also use it for corporate and other environments requiring high reliability/stability. Thank you to the developers!
Also, on Windows, the daylies are faster than any other PDF app I’ve tried (including all the big players and some lesser known ones). The only app that is as smooth and responsive is Preview on my macs.