I remember trying Opera for the first time in Windows 98 SE. It was one of those versions that prided itself for fitting on a floppy. I think it was 3.0.6 or 3.6. But anyway I was taken by surprise how good it was in comparison to Internet Explorer which at the time was the only browser I ever used.
Everything else after opera dropped Presto and became a chrome clone felt like a downgrade to me. I never got the same feeling of easy of use and control over a browser. I kept using the 12.16 for as much as I could, then switched to firefox. The new "opera browser" now is a different browser just sharing the same name.
And the beloved opera mini for the mobile was amazing. Back then I would even use it in a vm on my computer sometimes because I had shitty internet (and to use a proxy).