I’ve recently swapped over to road pedals on the road bike, rather than mtb spd’s that I had been using.
I’ve got these ones:
http://www.merlincycles.com/shimano-pd-r550-spd-sl-road-pedals-63269.html
and they work as you’d expect really.
The only annoyance that I hadn’t really considered is that road pedals are only one sided and aren’t weighted to always present themselves clip-in side up. I find this a pain, when pulling away from lights and stuff. It can take a bit more foot twizzling to get the pedals the right way up, than mtb pedals, which were just ‘stand on pedal and off you go’.