Qinux Watis portable heater: first impressions and practical questions

Hello everyone,

I bought a Qinux Watis portable heater online and have been using it for a couple of weeks. It heats a small room reasonably well and is easy to move around. I have a few practical questions: does placement near a wall affect efficiency or safety? What settings do you use to balance warmth and electricity use? Anyone with long-term experience (over a year) — any issues to watch for?

I appreciate any straightforward advice.