Took it out today for a 14-15k walk.
Very impressed with performance, I have never seen so many sats locked on before!
It was in my hand during the whole trip with the screen constantly on so I could review the screen in different light conditions and generally play with the unit. Got to say that even with out the sun filter selected the display was readable all day.
After being out for 3.5 hours the supplied rechargeable battery level only changed from solid green battery to a battery with four green bars!
Now to put in place a device to attach to the rucksack something akin to what Parky has done.