Burndy is a manufacturer of crimp style connectors, just like Cadwell is name of exothermic welded connections.
Yes I have allowed crimp ground grid connections (mine were from Thomas and Betts) instead of welded ones. In Wisconsin in the spring it is hard to find dry periods for welding, so the crimp style could be done "on demand" rather than scheduled.
I allow it's use as long as it is Burndy Hy-Ground products and the appropiate Burndy compression tools. The tools are expensive and not for the occasional user. Bu tif one is doing a lot of it, it is very fast and precise.
In my case, they are the preferred method; i.e., I spec them. (I was one of several Proposers to get recognized in the NEC).
My bias was developed at a jobsite where we could not get reliable exothermic welds on conductors #6 and larger. Even the manufacture's representative, after spending two days with us, (to show us how to do it right) had no better success then we did.
The welds were often incomplete and had both external pits and internal voids, to the point we couldn't develop confidence that the cross-sectional area was adequate for our needs.
This was a LONG time ago. I'm no longer quite as adamant.