systemd is free software: anyone claiming there is a spyware in it should
point out where. Nobody did.
systemd is quite well designed, at least better than the other init systems
that are available: that is why all major GNU/Linux distributions (including
the Debian technical committee) have chosen it by default.
systemd is quite stable: Fedora has been running it by default since May
2011; Mageia, openSUSE and Arch since 2012. Debian stable has been using
systemd by default for almost a year. The self-declared "Veteran Unix Admin"
behind Devuan were forecasting a great exodus (of developers and users) from
Debian towards their fork. It turns out it simply did not happen. According
to Devuan's website, "the current release series is ALPHA2 meaning not ready
for production" and version 1.0 should be released in... 2015.