There's a lot to be said for a nice chunky set of BMX pedals if you're going to use flats. Pins are good at improving grip, but aren't kind to either shoes or shins.
I was pretty wary of pins when I started using flats again about three years ago, both for my shins and shoes, but those fears have not been borne out by experience:
- I've never had more than a tiny scratch from them. OTOH I have really hurt my shin a few times when I've not clipped in properly and the pedal has swung round hard.
- And I'm still using my first pair of Five Tens after several thousands of miles. The inner has worn some holes and may well wear out before the sole!
I've found pins to be Not Kind to my default Doc Martens. I suspect there may be p*nct*r* fairy involvement. But they did greatly improve grip, which Docs aren't known for.
Shoes wearing from the inside out is normal and ordinary for me. The notable exception was the walking boots that developed leaks from prolonged riding in PowerGrips, before I took the plunge on SPDs. With clipless, the wear is concentrated on replaceable parts of the shoe (cleat and insole, respectively), which is a point in their favour, as I hate shoe shopping.
It's been a long time since I bashed my shin on any kind of pedal (which probably means I need to do more off-roading). I have given my Achilles a good whack on the tyre during an unplanned unclip on the recumbent a couple of times, but that would happen more frequently if I tried to ride it in flats.