Strengths: Small and unobtrusive even on small wrists, good to go straight away, no recharging.
Weaknesses: No mapping of route, lots of separate parts.
Overall: A fantastic option for runners who do different types of training. I know that I can use this just as effectively on a slow club run, a quick jaunt on a treadmill or a run through thick trees or tall buildings.
The lack of software with it is a bit of a disadvantage, though the real-time pacing info works really well - it's nice and smooth with few if any spikes.
I found the footpod was quite inaccurate out of the box, but calibrating it was easy enough and it is certainly far more accurate than most treadmills now.
Overall: I was initially put off buying this by the cost and fact that they look so bizarre, but bought one recently and the support is amazing (i'm 32E). Shock absorbers etc don't compare - and I thought I was happy with what I was wearing before! Feels a bit tight at first but soon forget I'm wearing it.