Hydraulic discs are absolutely out of the question! IMO, something that hi-tech/complicated is major overkill for anything but true mountain biking. While I might encounter some rough dirt roads, I don't plan on doing any serious technical/trail riding.

You have given me pause to consider mechanical discs. I'll do more research before making a decision, if discs are truly unlikely to be damaged and/or fairly easy to repair, I'll be more inclined to go with them.