Really? Surprised an app for a file format designed primarily for printing would have issues with printing. What problems are you seeing?

AFAIK, Sumatra still internally renders the entire page as a bitmap in order to print it. This results in huge jobs being sent to the printer and extremely slow printing.

It also seems to have some odd behaviour in its rendering process, though I've never been able to identify exactly what it is. For example, a plain black-and-white document I printed the other day looked extremely fuzzy, like the early inkjets that only had CMY ink and could only produce "black" as a muddy combination of the other colours. The same document looked normal when reprinted using different software.