aha I see.
Looks pretty good, don't know anyone with one, worth finding somewhere/someone with one and having a play.
The 725:
http://www.polar.fi/en/products/multisport/S725XYou're right the cadence isn't essential, although it is nice to have it displayed on the screen all the time and you can notice immediately if you're slacking, and it's quite handy if you're aiming for a particular cadence to glance at rather than try to count.
Quite cool to look at the download data later and see how your cadence/speed/power etc change with altitude, you can look at a climb and see where you were doing o.k. and where it all fell to pieces.