1x9 and 1x10 work fine too, for little or no extra cost. The trade-off is there may be some real grunt climbs that'll have you pushing every now and then. So far it has not been enough to make me want to drop $100 on a 42t cog.
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Originally Posted by Mark Twain
"Don't argue with stupid people; they will drag you down to their level and then beat you with experience."