It'll come with all the info Jay, I have a Foreunner 50 and they're great!! Once your set-up and start down loading your runs you'll find loads of little bits n bobs you can do!! I think the 305 is GPS(??), if it is I think i'm right in saying it'll show where you've just run and all the associated data!!
You can also share the info through the Garmin website and check other peoples routes, compare notes etc..... the Garmins are a great piece of kit. I'm thinking of upgrading for christmas so I have the GPS function!!
Oh and you can also download training plans found on this site!!
ie here's the download for a sub 4hr training plan:-
http://www.runnersworld.co.uk/news/article.asp?UAN=2765
Edited: 14/10/2009 at 23:26