Although Safari may not be perfect, as far as truly native iPhone browsers go, it's all we've got. If one of your major problems with Apple's mobile browser is how long it takes to load, you're in good company.
It's Safari's built-in session saving feature that makes the browser so sluggish. In most cases, it will completely reload you're previous page you were on at launch. iOS doesn't have an option to disable this feature, but there might be a way around it...