Weaknesses: I hate the touch bezel, it would be a far better product if it just had buttons. The battery life is very poor, you have to check it before every run to ensure that there is sufficient battery left to complete your run. To be honest I already own a 305 and only bought this as I thought it would be better as its smaller during my marathon training. I now almost always use the 305! At least it is easy to use and the battery lasts!!