uhh, not to be a dick but your REALLY clueless. first off, if your ride is flat and you really wanna be hip ride a singlespeed- thats the only reason anyone knows about theme these days that hasnt ever biked before. if its hilly, ride a geared bike, the wide range of different gear ratios makes it easier to climb hills while at the same time allowing you to get a gear ratio that is suitable for fast flatland riding. also, youll always sweat, just depends on your body. ive been an avid cyclist since before i was a teenager and today i race at a high college level and even on my 3/4 mile commute to class i sweat a lot, even in the cold pittsburgh weather- just happens. also, what bike is your geared one? if its a piece of **** old bike maybe invest in a new bike if you plan on riding a lot-old parts can be worn out and henceforth slower. but neither is "faster" it just depends on what gear ratio your using. only after you have ridden a lot of bikes and for a while can you tell if one thing is faster than another. read this website for EVERYTHING related to bikes EVER http://sheldonbrown.com . just browse and search and youll be a bike expert in 2 weeks, even if you cant ride well