For web browsing, the bundle is the definitive, closest-to-actually-being-secure way to do it. Tor's FAQ explicitly calls what you're doing "a really bad idea." I'm too lazy to write down all the ways it is a bad idea, but I'll just summarize it to say that you can't make Chrome always use the proxy, and it's still possible in various ways for a site to induce Chrome to give up information about you.