as a frequent traveller and someone interested in specific run goal , -lrb- as oppose to `` just go out for a jog '' -rrb- the Forerunner 305 have be extremely helpful . my wife originally get I the Forerunner 405 BUT it be too small for my wrist . -lrb- the 305 have a larger , alternate wrist strap -rrb- . my wife refer to the 305 as a `` laptop for the wrist '' but it be not heavy or cumbersome - the button be clearly marked and easy to use . the various training workout be helpful and easy to program -lrb- pace \/ distance \/ time \/ interval workout ... -rrb- . I have have no problem with the gp - just remember to turn the unit on when you be outside and ready to run -lrb- to ensure GPS reception -rrb- . aural alert be helpful and there be enough function to check out that can keep you occupy on long run . I have not explore all of the training or navigation function on the 305 but I would venture to say that there be more than the average runner would need to use .