I concur with the nods towards Garmin.
I have a Garmin Edge 200, it's good for plotting routes and uploading to strava (or wherever) but doesn't do much else. However it's a hell of a lot cheaper than the current range (510,810,1000) so I think it's ideal for a first purchase.
Edit: Oh and definitely go bar mounted one, the bigger screen size is a lot more helpful if following a course - plus it just displays more information without constantly having to press buttons. The watches are more targeted towards runners.