I've downloaded into Training Centre and uploaded to my 610 previously. The Garmin VLM ready plan is out of date, the download file has a previous years VLM start date, so although you can load into training centre, it doesn't schedule the workouts.
Garmin lso have some marathon training plans on their website (look for 'full potential' / garmin.com/summertraining) These are all heart rate based.
Personally I lasted about one week with my watch beeping away to speed up or slow down, so like Steve C, I "free-ran" then
Edited: 17/12/2012 at 23:26