I have not yet used Stoner Trim Shine on my engine bay, but I know that many people do. Last spring I was trying to decide whether to purchase one of the Stoner sprays or CD-2, so I wrote Stoner and they immediately got back to me. Here is what I learned.
The active ingredients in Trim Shine, More Shine (tire dressing), and More Shine (interior dressing) are basically the same; but the products give slightly different looks. I gather that the tire dressing may be a tad glossier than the other two. The big difference, though, is the spray patterns of the three products. The interior dressing has a mistier spray, whereas More Shine (tire) and Trim Shine have a coarser spray. I was told that some detailers prefer the interior dressing spray pattern.
Finally, the guy from Stoner warned me not to apply any of their aerosol dressings to a HOT engine. The propellant in them is flammable. And since the dressings contain various oils, one should be careful around belts and the alternator.
I wonder what the differences are between Stoner Trim Shine and CD-2 Engine Detailer. They seem to be similar products. I telephoned the CD-2 customer support and was told that CD-2 is a petroleum-based product; but it was clear that the support person really had no understanding of the product whatsoever: she was just reading from a computer screen, and so I do not know how reliable the information is. I do know that I like CD-2's ease of application and the look it confers.
Al