Strengths: easy setting nice big read-out on big screen lots of laps
Weaknesses: chest straps eats batteries like there's no tomorrow (user replacable, so not too big a problem) coded/analog signal but the analog doesn't seem to work very well with fitness equipment in my gym Not suitable for small wrists at all, it's a very chunky unit.
The vibra-alert is a bit of a gadget that mainly consumes as lot of watch power, I believe.
Overall: I'm happily using it and it's good for simple workout zone monitoring and taking split times, but to be honest I got it with a loyalty point scheme and would maybe not spend £70 on it. It depends on what you want as always. The readings are very easy on the run because of the big screen, easy to flick between HR+chrono, HR+time, HR+lap on the run, but maybe the cost in terms of size for this unit is a bit high.
Some people might like the calories and fat burn read-outs, but that's to me just a fun number to see after a long run.
Been using it for a year and the HR-readings are good, I hardly ever have freak readings or bad contact and when I have a problem, usually the battery hasn't been inserted properly in the chest strap, easily resolved.