I agree the thumprs work, short on lift imo but they make power and ton of low end. I liked the hydraulic haulers but dont forget the lunati streetmaster series, they had a good amount of lift for the duration and a 108 ls.
This is basically the same thing I've been doing for a long time. Installing 284/484 108LSA camshafts at 100-102 in any 340-360, high compression, low compression, doesn't matter. It WORKS, end of story.
I've seen PLENTY of 340-360's with the same cam installed straight up that run like garbage on the street. Bad idle tune up all the way up. Just junk. Turned some of them around, others couldn't be bothered with a way to make it work and blamed the poor cam selection. Sometimes you have to figure out how to make what you have work.
Thumpr, whiplash, rattler all are the same principle. Longer duration, tighter LSA and install way ahead. People have been doing it since the 60's for sure. Not a new concept.