Locale and tasker look pretty cool. How much effect will they have on battery life?

In a similar vein to this question, I'm interested in finding any useful recipes for Tasker. I've found several profiles and "Step Throughs" on their wiki, but would be interested in any others that people have found helpful.

Using 'Tasker', I have a task set up to dial my mobile phone balance enquiry number at 7pm each night, put in the right options, then hang up. That results in a text being sent to me each evening with my remaining minutes - great! However - I'm about to go abroad for three weeks and, left in its present state, it will rack up quite a bill if it does manage to dial. How can I make this action …

For general detecting circumstances and triggering actions, what are the advantages/disadvantages of Tasker and Locale? Which one does the best job overall capability for improving the usefulness of a phone/device? Categories of particular interest (in no particular order): "Recipe" power "Recipe" ease-of-creation Variety of circumstances that each app can detect Actions and configurations that can be triggered Backing up setup Sharing configuration