I'm looking for distance flats that are very durable or maybe come with a removable insole that can be replaced after a while. Things like that. It doesn't even have to be a true flat, but definitely something that I would use for both racing and training and that's close to minimal without being extreme like VFFs. Something like a Pearl Izumi Streak or Mizuno Wave Ronin is probably on the most built-up end I'm willing to consider, so anything from that to a true distance spike would be what I'm looking for.
I've heard that the NB100s are worth taking a loot at, but haven't heard many details about them. I tried on a pair of Nike Zoom Streak 2 and thought they were okay, but I seriously questioned their durability. Any thoughts?