I discovered that a construction window caulking is virtually the same product but at a very favorable price advantage.
The product is called FLEXTRA* and comes in standard caulking gun tubes.
I have used it with great success whenever I want to 'glue' dissimilar products.
Just be sure to have squeaky clean surfaces.
Since it is flexible it is great for dissimilar materials that have different rates of expansion.(like glass and metal)
It also isolates the glass from vibration and shocks.
Sticking 2 pieces of (metal) and you need a cold chisel to separate them, that's how good an adhesive it is!
* that is one brand, but other urethane caulks do exist.
I think I will look into this flextra and see how it works.
Thanks for all the ideas and recommendations.