I'd recommend waiting. KMS got a patch recently that unlocks each one automatically after you hit a certain level and do a quest. No sense in wasting time grinding for honor when you'll be able to do it much more quickly in the near future.
Not really sure how much or how long, though I am finding it easy to get exp. I've been running the Defense one on hard solo, and it's netting 4500-4650 honor exp per 7 minutes an it's fairly easy to do. It's gotten me to near 20 so far without any problems, no idea if exp requirements starts to spike in later levels though.
Playing: Eternal Darkness Sanity's Requiem, Muramasa the Demon Blade, Sly Cooper and the Thievius Raccoonus (PS3) PSN: jext77