Eugene_uaI was under the impression it was the reverse as micro has the springs on the cable, mini has the springs in the socket. Cables are far easier and cheaper to replace than the sockets when they wear out.
Eugene_uaBut ya know what, I don't think it matters much at all. The keyboard isn't going to be plugged in/out all that often. Just a minor annoyance of having so many different types of cables.
Eugene_uaMicro is actually the best choice of USB connectors for nearly all practical purposes and intents.
"The newer Micro-USB receptacles are designed for up to 10,000 cycles of insertion and removal between the receptacle and plug, compared to 1,500 for the standard USB and 5,000 for the Mini-USB receptacle. This is accomplished by adding a locking device and by moving the leaf-spring connector from the jack to the plug, so that the most-stressed part is on the cable side of the connection. This change was made so that the connector on the less expensive cable would bear the most wear instead of the more expensive micro-USB device."
Source: https://en.wikipedia.org/wiki/USB#Durability