I also have the SPD-SL R540s on my road bike - they are the pedals it came with and I see no reason to change. They do the job and I certainly prefer them to the old style Looks on my previous bike

This thead looks like it is mostly about road bikes but for what it is worth all my pedals are shimano at the moment - I have the 324's on my commuter and the 525's on my mountain bike