I just started using Opera yesterday
I downloaded Opera back when an Opera CEO said he'd swim from Norway to the US if 1 million people downloaded Opera 8 in 4 days. I used it for a day or so and then went back to Firefox I don't think there was any real reason why I quit using Opera 8 I probably just stopped using it because I didn't have it set as my default browser
. Yesterday I decided to upgrade to Opera 9 and it hasn't caused me any problems so far.