Strengths: It's got almost every function you could wish for. The supporting software is a bit clunky but allows you to interpret the data in a variety of ways. Being able to change the watch settings via the PC interface is easy and very useful.
Weaknesses: Information overload! Unless you're really into the subject you'll probably never use all the functions. Software is started to look dated with a limit to the number of comparisons you can show on a chart.
Overall: This is a fantastic HRM. Has lots of features. If, like most people you just want to be able to see how your performance rates over the same course then it will do it admirably. But there's so much it can do and you'll have to ask yourself whether you'll ever need or use them.