So I'm in a bit of a strange circumstance at the moment.

I have a road bike that I've ridden for a while and a newer commuter bike (flat bar road bike). I run SPD-SL on the roadie with a set of roadie shoes that I like and spent forever trying to find a pair that finally fit.

Now I was planning on running SPDs (mountain bike pedals) on the commuter and get another another pair of shoes. I already have the pedals but I am finding it a lot of trouble to get a pair of MTB shoes that fit happily. I took a chance and ordered a pair from overseas that wasn't available locally and still they don't fit properly. I must have weird feet.

So now I'm just considering using road pedals with my existing road shoes on the commuter bike. I even have a spare pair of RD-540s around somewhere.

Now I don't really plan on doing a huge amount of walking on my commute. But frequently I catch the train part way and it's the walk along the platform and up the stairs on the overpass that would make the MTB setup more practical.

Should I just stick with my road setup and sell of the MTB gear I already have. Or keep trying to find some shoes that might do? Or is there another option?

Sidi has the most different sizes of any off the shelf bike shoes out there ..

Spud shoes recessed cleat is a better walk , but the regular shoes are better yet,
so I dont use the clip stuff much any more ..
The Rubber Bean boots in the winter are where I keep my feet dry,,

You already spend a lot of time, energy and $$$ finding something that works. Don't change it. I see no reason why you shouldn't use the same type pedals on your commuter. Why are you contemplating SPD pedals for your commuter?

If you are having a very hard time finding shoes that work for you, then maybe using the SPD-SL pedals would work okay. Sometimes I ride a bike with SPD-SL pedals to work and bring regular shoes to change into, but on the weekend if I'm going into work for only an hour or two, I'll just walk around in the bike shoes. Not a huge problem, just can't run very fast in them...

It should not be that hard to find good fitting Mtb shoes. Different styles vary considerably in their fit, and some will be right for you. Can you go to a store that has a selection to try on? Commuting in spd-Sl shoes sounds like a nightmare to me.

There was a guy that used to commute on train with me. He was wearing the Look Keo or something and tap dancing through platform/3 flights of stairs up and down every day. It definitely is more than doable. For me, I prefer not to change shoes. So my commute is SPD sneaker such as Chrome Kursk or DZR shoes... (Do have a six six one SPD filter... don't like the look much ) My leisure ride is SPD still using Shimano R-087... (soon to change to MTB shoes for stiffer soles).

First, is your commute really that long/hard that you need to clip in?
If so, you might look at some of the regular shoes with SPD cleats - I know Keen makes a few, I think Chrome might also.

Road shoes suck to walk in.

Here's a couple of options:

1. cleat covers for your road shoes - might help with walking some
2. There are sandals that work with SPD cleats. Might be easier to find some that fit.

SPD SL are a single sided pedal, there are some platform SPD combo pedals.

Or bring a walking friendly set of shoes, velcro and buckles on Road shoes
come off quickly.

with the cleat above the shoe sole , the cleats wear out sooner.

Sandals aren't just for warm weather riding either. If you get them on the large side you can wear a pair of socks or two that are designed to help deal with cold and wet.

It was in the mid-30s here this morning and I wore my Nashbar SPD sandals with wool socks. I had gotten spoiled on them again the last week or so when it was so warm and I didn't want to go back to the other SPD shoe options. Toes got a little chilly, but nothing more than I expected.

You can augment the sandals with a shoe cover , and get more rain and wind blocking.
and pack them away when not needed ..

Touring riders have liked shimano's Spud sandals for the versatility.

Easy for you to say if you don't have size 13 4EEE boats for feet.

throw some seal skinz over those wool socks and you're good down to at least 20F

Only 99% ??