I found the axle on stamps too pronounced in comparison to the rest of the platform, but I think they were at the low end of the stamp range so maybe more expensive ones don’t have that issue.
I've got both the Stamp 1 and then payed up for the Stamp 7. Can't say I noticed much, although they bigger allen "spikes" seem to work better with my Shimano shoes compared to the Stamp 1 pins.
I found the axle on stamps too pronounced in comparison to the rest of the platform, but I think they were at the low end of the stamp range so maybe more expensive ones don’t have that issue.