I've had Polar products before and they're always reliable and well designed.
I chose this watch as I wanted to use the HR monitor to guide my training not just monitor it. The watch has built in training programmes, it calculates your optimal heart rate zones, and gives you continuous feedback about your training zones. Using this I'm training smarter rather than harder, and feel better for it. No longer do I have sessions where I quit half way through, because if I do what the watch says I'm training intelligently rather than over-doing it. I honestly think that for years I've been going at it too hard and consequently training my anaerobic metabolism rather than building a sound aerobic base.
Apart from that the watch looks good and can be used as an everyday timepiece. There are 2 or 3 versions available though - I hear that the one with the red screen can be difficult to read. I didn't get that one.