How practical are clipless pedal shoes on a long bike tour? In the last years I did a couple of long bike tours. So far, I always had platform pedals with pins on my bike and I've worn &quot;normal&quot; shoes. For my next tour I'm considering clipless pedals. I have only recently started to work with these type of pedals. So far, I suggest that SPD pedals would be the best choice. My concern is that I don't want to take a second pair of shoes with me and that the SPD pedal shoes are not good for walking and being in nature in the evening and morning.
Are there SPD pedal systems with shoes that are practical enough for that? With practical I mean:

They are nice to walk
They are robust against weather
The cleats on the shoe are robust (I'm going to be in areas without a proper bike shop)
The pedals are robust too

In general, I'm not sure if it makes sense to use SPD pedals on long bike tour. Is the performance increase worth it? Or is it more clever to use platform pedals with either pins or a strap as they are more fail-proof?
They are nice to walk

Proper fitted MTB shoes with SPD cleats are quite comfortable to walk in, at least for non-marathon distances (say, less than 10 km a day). They are still less ideal when compared to normal walking/running shoes, however, for these reasons: 1. They are stiffer than regular shoes.
2. They have less gripping surface because the metal plates do not grip at all.
For really long tours (weeks) you will want to have an additional pair of comfortable camping shoes, crocs or &quot;slippers&quot; which you put on at the end of the day of cycling.

They are robust against weather

There are even MTB boots with SPD mounts, meant to be used while fatbiking in snow and well into freezing temperatures. You will have to strike a balance though: 100% waterproof things will be extremely hot in any other non-rainy day, and vice versa, breathing shoes will become wet in a thunderstorm.

The cleats on the shoe are robust (I'm going to be in areas without a proper bike shop)

Cleats are not coming with shoes, they are bought separately or with pedals. You can have a pair of spare cleats with you if you are concerned with their reliability. Do not forget to take spare cleat mounting bolts as well: it is more likely to lose a bolt than to break a cleat.

The pedals are robust too

SPD pedals are organized the same way as regular platform pedals, with a couple of extra springs and pieces. They are therefore as robust in their construction as the platform pedals. The locking mechanism can of course fail or become damaged. If you are concerned with such a possibility, pick a pair of SPD pedals with a small platform (compare e.g. Crankbrothers Candy and Eggbeaters; the latter are very minimal, the former ones have platforms), so that you can continue using them even if the spring fails. Alternatively, there are two-sided pedals that can be used as regular platform pedals on one side and as SPD pedal on the other. This way, you'll always be able to continue the journey.