That looks great at first until I tried searching and I got hit with a low-res captcha asking me to choose pictures about minecraft because /g/tards bots are stressing the server. I don’t get that on SearX.
Also, the server is in the US, privacy-wise, that’s quite bad.
Browser private modes are not really private, it’s just an isolated window that won’t save your search to the browser history. Google and other trackers would always link your private session back to you.
Read Mozilla’s take on browser private modes.