SPD's are great to start with. You'll notice the difference right away. The double sided ones look fine, but you'll have to flip them over to use the platform. Also I suspect you'll start taking your bike shoes whenever you ride, and carrying other shoes to change into. That's just how good they are.

Slack them right off when you get them, then if you fall you'll get your foot out no problem. In a few weeks, tighten them up so you don't pull your foot out by mistake on a climb.