ok you're on. I'll get this up as soon as I get a moment.
Off the top of my head Legend. There are very few NWOBHM bands that can even stand up to 'From the Fjorns'. And I would even say to some degree The Rods. Certainly would go with Justin's suggestion of TKO.
By 1978 America was focusing on more Slade / The Sweet influenced stuff but still there were "heavy metal" bands all over the US that were just not going to get the attention Britain was.
You and I also see that period differently too as we have disused before; you see that it begins and ends with the leaders of the movement where I on the other hand see that it went beyond Diamond Head and Angel Witck, though it was stretching in many cases.
Oh and 'Search for Sanity' is usually not the album being referred to when talking about Onslaught as a thrash band; the first two albums were almost like a different band.
I don't see it differently, we just argue over what bands would truly be considered a part of it and Grim Reaper will never be a part of that in my book.
As far as US audiences that is THE Onslaught album they are talking about. It was on a major label and videos were on MTV.