There is a product made by VisibleDust that is spefically targetted to remove oil and other stubborn stains called Smear Away - they have two others for lesser problems such as dust. I have not used it, so I can't speak from personal experience, like you I have only used Eclipse, but this is a very good company that makes quality stuff.
http://visibledust.com/products3.php?pid=303

I can vouch for their new Quasar Sensor Loupe - it works amazingly well. I got it about a week ago to use on my first D800 sensor cleaning. I found a lot more dust on the sensor with the loupe than I thought I had from test images. I went through 5 Sensor Swabs with Eclipse before I could see that it was litterally spotless. And I could immediately see whether the last swab had completely cleaned the sensor or not. The first swab made things worse, but the next four got progressively better. It's more expensive than some other loupes out there, but I can tell you this one delivers as advertised.
http://visibledust.com/products3.php?pid=602

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Dave Badger
Blacksburg, VA

www.AlternateViewsPhotography.com

"You don't quit playing because you grow old; you grow old because you quit playing." (And now a grandson to share my toys!)

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