For about two years I have been using Shimano SPD (Shimano Pedaling Dynamics) A530 clipless pedals for bicycle touring and have become a fan of clipless pedals. This year I have switched to the M324 and I personally like them better. There are several reasons.
Before going into that, I need to present my clipless caveat. There is a learning curve with clipless pedals and involves falling down at least once in the process. I tipped over on my bike at least three times when I was learning to use the pedals. You need to plan ahead and unclip when stopping or when there is a possibility that you will need to stop. If you don’t, you come to a stop and tip over.
Both of these pedals have a clip side and a platform side, which in my opinion is a requirement for touring. The difference is that the A530 has a cast aluminum platform and the M324 a stamped metal platform that is integrated with the aluminum frame. The advantage of both is that you can ride without the special shoes by using the platform side. Sometimes it is also desirable to avoid the clips when you know that you may need to jump off the bike frequently, such as when going up a steep hill with a loaded touring bike.
The pedals are equally easy to use. I am able to find the clip side without a lot of hunting and without looking down at the pedal. If you use clipless pedals, you should develop your own technique to find the clips without looking because looking down at the pedal and messing around trying to flip it to the clip side is a dangerous maneuver.
The platform side is a different story. The A530 is best suited for occasional use of the platform side rather than a long ride. The platform is large enough, but it does not provide enough gripping power to prevent shoes from slipping off. The cast aluminum “nubbies” on the platform surface are not aggressive enough to grip the bottom of shoes.
The M324 works very well on either side. This week I did a 25 mile training ride using the clips with my Shimano shoes and another 25 mile ride using the platform side with cross training shoes. The platform side of the pedal gripped either type of shoe with no problems. The good news was that the platform side was secure and comfortable for a long ride. For me, that is very important when riding hills on a loaded bike.
In the past I have deliberately swapped the clipless pedals for platform pedals, depending on expected tour or training conditions. I have even carried pedals with me on tours in case conditions warranted one type of pedal or the other. With the Shimano M324 I am confident that I will not need to do that anymore. In my opinion, the M324 pedals are great for all kinds of bicycle touring conditions.