1. No.
2. Go for enchanted, though you may want to keep the steel one to enchant later. Then again, you'll most likely find better material stuff. Anyway, yes, after ten strikes, the weapon no longer deals additional shock damage. It will still harm ghosts and it's like though. To recharge. Visit your local enchanter where he will recharge it for a price... or use a filled Soul Gem to charge it yourself.
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Aww, I lost to SuperNiceDog, Winner of the Rivalry Rumble Guru Contest