I use 305 for running (long distances and intervals) and cycling (mostly watching my cadence since I'm new in cycling). The only complains I have are:1) It takes long time for it to initialize GPS. Sometimes up to almost 3 minutes. Not good when it's freezing or raining outside.2) I wish sound level for beeps is louder.3) Some minor issues with their PC software (mostly related to saving/importing workouts), nothing serious though.But onve again - 305 is just a great device!