It is not a bug, but something that disqualifies it (IMO). It's not only when you use the back button - it's also when you use the "Homepage" link (for example). That way the page may load faster, but on busy websites (like forums or blogs) this browser is not useful.
Another issue - whenever I initially load Opera, it loads 3 times slower than IE or FF. It's not something welcoming to the user either.
My experience with Opera is 180 degrees opposite yours, menial. They've been THE innovator in modern browser development with features like tabbed browsing and an integrated feed reader. It's got a relatively small footprint, and the interface is extremely customizable.
I've often said that using Opera gives me an extra hour in every work day, and I still feel that way. Even Firefox has me locked in to some behaviors that Opera allows me to change to my liking. Opera is my main browser (and I'm on forums and blogs a lot) and it has been for years. I use Firefox for some of the useful add-ons, and IE (when I must) for testing purposes or for some financial sites that require it. I definitely use all 3 browsers every day, and Safari a couple times a week.
To answer your question about the cache, you can set the Opera cache to behave according to your preferences, and in some very fine-tuned ways. For example, it can treat the caching of images and documents on different time scales, ranging from "never" through minutes, hours and days, and up to "always".
Look under Tools > Preferences > Advanced > History for the options.
"Look under Tools > Preferences > Advanced > History for the options."
That seems to have done the trick. Don't get me wrong, I like Opera too - their "Author's mode or RSS subscriptions" are very useful. It's very fast when browsing too. Maybe they could revise their default settings as most users don't usually change them. Thanks for the tip.