Yes. This one comes with GB maps.

Yes, but you need to download BaseCamp from the Garmin site to do it on the OS maps and the Edge needs to be connected to the PC while you do it.

Can use MemoryMap as well.

Once a route is in, works just like a car sat nav. In fact you can use it as a car sat nav if you want to.

It does, but the ability to locate by postcode is not up to the standard on say a TomTom, neither is the number of POIs. However, it is relatively simple (using BaseCamp) to add your own locations for well used places - home. places you've visited and so on.

Yes its just like a car sat nav with OS maps rather than a road map

The os maps that come with this do not let you plot a route its more of an aid to follow routes that have already been ridden or downloaded to the device. You can plot route though from various web sites then send them to the device using garmin software..

Yes, it has a 1:50,000 OS 'Discovery map loaded on a micro SD card and the unit has the facility to select 'Go To' on the map and it plots a route for you.

Yes but plan view not 'forward looking aeroplane view' like you can do on Tom-Tom. Works well though and lets you know what road and direction you're travelling and what turnings are coming up.

The free Garmin BaseCamp s/w works with the device to allow you to plot routes on a PC, and then download those routes to the device.
It requires the device to be connected to the PC so that it can access the O/S maps.

Yes, but I use MapMyRide to create the routes and import them into the 800.

yes, but silent, no voice

No it doesn't. I bought the same bundle. It only comes with the detailed ordance survey uk map pack. Wiggle sell the premium heart rate monitor seperately.

No this package does not come with the strap.it is a extra item you may purchase later. I believe the proformance pack is the one that it come with!

No. Only comes with a Navigation package.

No, but you can buy it separately: http://www.wiggle.co.uk/garmin-premium-heart-rate-monitor-soft-strap/

No it doesn't.
Comes with bars mounts only

This bundle if just for the device and maps.
A different bundle comes with Cadence and heart monitors.

No, but you can buy one for about £40 and it works a dream

No, this does not come with a heart rate strap. The performance package includes a cadence sensor and heart rate strap but if you are after the OS mapping it is by far more cost effective to purchase the trail pack and an ANT+ heart rate monitor.

No, but you can buy the Garmin one separately

It works with any ANT+ sensors. I use a 310XT as well and the sensors will send to both simultaneously. Great for triathlon where you can wear the wrist unit for the swim and run and you also get a bike computer.

Not sure on the cadence sensor but I am using the heart monitor strap off my 305 and it works fine.

Mine work fine with it

I don't know if it will help, but my Garmin 405 heart rate monitor works with the Edge 800. I am sure the 305 and 405 heart rate monitor is the same. I don't have the cadence sensors, so I can't answer that. It is very easy to pair the heart rate monitor with the Edge 800 and it stays paired with the 305 or 405. I hope this helps.

yeh... you can change the routing settings to off road....

BUT ALWAYS TAKE A PAPER MAP as batteries run out especaly when your up a mountain in fog!

You can use it for walking too but you need to switch off the autopause mode for going at walking speeds. Also the screen can be a bit small to get a full perspective of a map.

yes I have found it just as useful for treking.

I dont see why not, it is a general gps system which has maps on it depending on what package you purchased. It works as a sat nav in the car and keeps up with road and off road cycling routes, i cannot see why it wouldnt aid trekkers, as long as the correct maps are in use.

Yes, if you export from MM as a gpx file then import it to Basecamp.

Yes you can. I've done this with memory map.

Japan
Yes I can

This will fit on your stem or your handlebars. It comes with enough fitments for two bikes so if you have more then obviously you will need more fitments (cheap). On my mountain bike it just fits onto a 70mm Easton Haven stem.

Mine fits on the handlebar stem quite easily and due to the elastic band fixtures, it's very easy and quick to swop the mount over between bikes.

if they are I didn't get one! (if you get one let me know and I'll be back to get one too!!!)
Good luck...

Answers on page 45
http://static.garmincdn.com/pumac/Edge_800_OM_EN.pdf

built in.. one charge lasts about 15-18 hrs

I reckon I charge mine once a week which is 10hrs cycling.... possibly less often than that even.

It certainly worked with the cadence sensor from my 305.

So yes, just new mounts