You don't need a power meter. A cheap heart rate monitor will do just fine for interval training. If you move to an indoor trainer get rollers. They will help you with your spin and bike control. Plus they are far less boring than trainers.
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I'm not one for fawning over bicycles, but I do believe that our bikes communicate with us, and what this bike is saying is, "You're an idiot." BikeSnobNYC