I use clipless. I first went clipless on my MTB even before I owned a road bike. I found it made a big difference, especially in climbing. Also it helped alleviate some knee pain I was having due to drifting into poor position on my platform pedals on longer rides. FWIW I have since switched to a combination platform clipless pedal on the bike I sometimes use for commuting. This saves me having to use bike shoes when I ride to work ( a short ride) but allows me to clip in for longer rides where it will make a difference.