To expand on other answers... I have used a variety of iphone apps, all of which failed to work accurately. The problem is that phone apps communicate indirectly with gps satellites, using the phone network. This works OK if you have a strong signal, but often you don't, especially if the phone is in your pocket. As anyone with a smart phone knows, the 3G coverage needed to make a navigation app work adequately is patchy (4G may be better but that isn't widely available yet). Also, a phone navigation or cycle computer app sucks the life out of your battery. At most you get about 5 hours from a full battery. Useless for all day rides. I gave up on phone apps some time ago.

In one word. Accuracy.

I too used the iphone app before buying a Garmin device so can compare the performance of both. I would quite often find my route straying off the roads and even gaps in the data when using the app. I also did not think that the elevation data was very accurate.

As a member of a cycle club i would also compare my Garmin data to that of app users and other Garmin users after competing the same ride. While the Garmin users were all very close with the data some of the apps were way off.

The final thing to think about is battery use. Get a Garmin and save the battery in your phone for emergency use. One day you may well be miles from home with a mechanical issue and need to make that rescue phone call.

Hi.
It gives a ton more features. Plus the Garmin connect site is very cool too. But what I like about it the most is the batter doesn't die on 4 or 5 hour plus rides like my iphone did. Check out the Garmin manual for all the features but if you're a serious rider who likes to keep all the stats (not just the basic ones) then this great.

The mains plug came with a main unit with 3 or 4 adapters to allow different plug/pin configurations. I do not know whether an Australian version plug is included. The USB lead also charges the Edge from the PC. I have only ever used the main to charge my Edge once in the year I have owned it as the PC keeps it topped up while I am uploading/downloading data and routes. A full charge should keep the Edge alive and working for around 15 hours. I have never seen mine drop its power reserve less than 70% on more than half day rides.

if you have an adapter for the uk plug then is fine otherwise just use your computer

Yes unfortunately a bit annoying as it comes with UK plug and a US one in box but not Australian. As you say you can charge through USB with computer or just use a USB plug to put the lead into. I just use my iPhone one.

Hope this helps.

Thanks

Thanks navy1

The iPhone charger suggestion is something I hadn't thought of.

I went ahead and purchased the Edge 500 and it came with all BUT the Australian plug, despite the instruction card showing it did...

Anyway plenty of charging options so no biggy.

If that watch accepts +Ant connections. Yes

Yes and yes.

Yes and Yes.

A simple spin lock battery cover needs to be removed and then a battery/ calculator size battery is needed. I have not yet needed to replace mine after nearly 6 months of use.

The display can be tailored to however you want. My default front screen shows total distance, average speed, current speed, cadence and heart rate. For me they are the fields i need on my training rides.

Obviously if you require different fields then you can easily change them in the menu system.

batteries?? not sure

cadence & HR simultaneously - yes
go to Settings setup and tell it which parameters to show in each screen position

yes you can change the batteries 2032 I believe.

You can also customise the data fields you want to display. I have current speed/HR/cadence/distance/and ride time all on the same screen

Yes to both. You can set up the display to show whatever data you like, spread across 3 seperate screens.

The battery in the GSC10 can easily be changed. It is a standard CR2032 type battery. See page 27 of the user manual for the Edge500 (available from the Garmin website).
Ditto for the heart rate monitor, same battery - see page 22 of the manual.
The display is infinitely changeable - you can easily change it to have both heart rate and cadence on the same page (max. of 3 pages, max. of 8 data fields on each). But note - if you use 8 data fields per page, the fields get a bit small. In my case I need my reading glasses - not very practical while going flat out.
Page 35 of the manual explains how to do this - press and hold MENU, select Settings> Bike Settings> Data Fields

Can batteries be replaced in sensors by me? = Yes "easy"

Can cadence and heart rate be displayed simultaneously? = Yes ,, you can have 3 pages of Data and up to 8 fields per page, you can choose any Data for any field "very easy to set up"