I'm cheap!!! I try to find the cheapest stuff to support my hobby, but luckily in this case, the cheapest has also turned out to be the best cleaner IMHO. What I use is a very simple home brew mix. Buy a gallon jug of windshield washer fliud (usually around a buck most anywhere you can find it). Squirt two or three good squirts of dawn dishwashing liquid in it and shake it. Pour it in your favorite squirt bottle and head to the field.

The dawn does a great job of cutting the oil, and the windshield washer fliud will do a great job of shining the plane without leaving a film on it.

give it a try, it's cheap enough so that if you don't like it you're not out much money