+1 on the Speedplay Zeros. There are different metals with different prices - so the Cro-Molys are significantly cheaper than the titanium, but they all use the same cleats, so you can keep your shoes for all your Zeros. The Zeros don't have the clogging issues that the Speedplay X's were reputed for having. I like that you can be unclipped but still very able to securely pedal, which is nice in traffic or in a mass-start at a ride. They do take a bit of breaking in for the first week or so - they take just an extra 'umph' to engage them. But after that, they're a breeze.
For 3 days, I get to part of a thousand other journeys.