Here is a link to what constitutes an Energy Star rating. Look it over and decide whether you want to spend the extra money.
http://www.energystar.gov/index.cfm?...ts.pr_how_earn
Methinks there is more to the difference than just the rating. Different brands? Both recognizable names? If I was doing an HGTV kitchen, I would not "cheap out" on appliances that I hope will last for many years.
Good luck with your project.