Mark,
I actually own a Threads License and a VB license. I can tell you I never put VB to use on a production site. I used it to test but here are my results. Threads is faster than VB. Now as straight out reason is the clunky coding in VB. VB appeals to the kiddies of the world cause its loading. Stuffed like an over stuffed sausage.
So speedwise for me it was Threads hands down there. Another reason I use Threads over VB is easy of use and customization. VB's templates are in a mysql database and you ever see their template editor and trying to find the right template it is a nightmare.
That alone was enough to keep me from every putting out a public version and keeping my site running threads. The two most important things to me were speed and ease of customization.
Put those two together and VB can never win. Rick is coding in some bells and whistles slowly but at a pace that it can be done correctly and not compromise the code.