Here's my full report of first rides.
I tried a borrowed set of Cannondale shoes and pedals, for a while, didn't like them, now got Shimano 520 and Shimano shoes that fit(Yippy) ,,,,,
No falls ,,,,,YET,, IF I DO THEY WILL COME OFF,, FOR GOOD.
I find they may help with efficiency.
They do help keep the feet on the pedals on them bumpy spots.
I now clip in pretty quick and out easy too.

They make me feel pigeon toed.
Several tries with and with out, they cost me 1 MPH.
As far as comfort goes, not impressed, but think the MTB with a wider stance would help.
But don't want em on the MTB, got no issues with feet leaving pedals unless I want them to.

The ONLY reason I got them was every body said so, and,, and,, cuz my feet won't stay on the pedals on the skinny tire road thing, so thats why I put em on it. I am thinking about them Pedal extenders......
**********?Pigeon toe problem**********