I compare him to other thrash drummers.
Dave Lombardo
Charlie Benante
Gar Samuelson
Chuck Behler
Nick Menza
Shawn Drover
Dirk Verbeuren
Paul Bostaph
John Dette
I'll even throw in Chris Adler because he was briefly in Megadeth.
I'll take all of them over Lars. He was great at following Diamond Head on tour and taking notes. He did a really good job of recognizing good musicians, and bringing them together. James is a really good rhythm player and does a good job adjusting to Lars' style. It was especially good back when they were still a thrash band.