Hard-bodied poppers on tubes have been around for quite some time. Bob's Banger is a foam tubefly that I believe Bob Popovic came up with many years ago as an alternative to hard bodied, tubefly poppers.

I have some great tubefly - deerhair poppers that Tom Travis tyed for me at a FFF South Eastern Council Conclave about 10-14 years ago. They were Tom's answer to tubefly hard-body poppers.