It's even easier with Opera; you just create multiple shortcuts with the
"-pd" (Personal Directory) switch.
The user that caused me to reactivate this thread also had Opera as well as Firefox. It took about 30 seconds to backup bookmarks and passwords through Opera Link, including automatic Opera Link account creation. Sharing with another PC took a few seconds.
Up to maybe a year ago, I was convinced that I should just promote Chrome - and that may yet be the case in future. Some sour Chrome releases have made me more circumspect; I still think it's good for low-powered PCs, but I'm not getting positive feedback.
All current browsers are badly flawed. The problem with Opera is that each release is just too incomplete to be a single browser solution. Otherwise, it's by far the slickest product, but IMO their QA is well behind Firefox (although apparently ahead of Google's).