I'll be honest when I ride my fixed gear conversion it's not for anything much over 10 miles tops round trip. It's a round town to the bar beater,library, drugstore etc. Now my plans on the 29er mtb aren't really set, other than building it ss to start. I may consider a internal geared hub down the line. or get jiggy with the welding machine and put a derail tab on it, not certain. I live in a pretty flat area for the most part so ss or fixed gear works to some extent....there are numerous people that ride commuters that are ss/fixed in the forum I'm sure you'll hear alot of more informed opinions than my own. Thing I like most about my fixed gear is leave it outside for months, it doesn't care at all. little lube and it's good to go.