@danieltaylor1, you have to understand the limitations of proxy browser architecture. When Opera Mini loads a page, it is a snapshot (let's simplify - a screenshot) of the page that was actually loaded on the server and adapted to your mobile device. That's where you are getting the speed from. Server compresses the craft, and send you back only the necessary data.
But that model has some limitations and disadvantages, the compression is lossy. That means some of richer websites features are gone. Ie. no fluid animations, no animated GIFs, etc. Also limited font sizing (that actually an old limitation from Java Mini times).