Joe, I just finished posting a reply to you on your other post.
The tie wraps are very secure, especially with the foam (heavy foam rubber) I put on the box to take any vibration. I think you can probably find a more asthetically appealing box but I had this laying around.
The whole assembly is very light so it doesn't take much to hold it but I was careful not to place the tie wraps over the entire box but throught it in an attempt to make it more secure. (in my mind anyhow)
Glad I could help you and Bob.