Strengths: Accurate distance readings, great for workouts, interval sessions etc. HRM is good to gauge how hard your working out etc
Weaknesses: The signal - When your surrounded by lots of tall buildings or when running through a wooded area it tends to keep telling you "weak signal"
Overall: Wouldn't do without it now, I'd feel naked!! It not any heavier than a normal ryunning watch and after a couple of runs you forget about the size. Would reckomend it to anybody. Very tempted by the 305 as well now.