Like Rotterdam said. It's not only the DX-100 and Heil or Bandshee, it's the performer. It took me a long time time get a good sound doing it.
Roger used the Hard Brass from the DX-100 and make sure you put it in Mono for lead lines.
Also when you do backgrounds, you have to do them like a singer and do about 8 to 16 parts. That's what Roger did as well. It's really a lot of work to get it right. It took me around three years to get it down. A great mic helps as well. I use a U87 Neumann.
He use to use a Shure 57 among other mics.
The best bet though is to make one or have one made. Same as Roger, And Teddy Riley whom is the new king at it.
Hope this helped....Check out the website. I think I still have a song that I did Talkbox on. I did that about 2 1/2 years ago.