John Grimes (A Bertram Chandler) - a little help?

I was looking at my shelves for something to read next, and I realized I have roughly a dozen novels set in the Rim universe. A few feature Derek Calver, set before John Grimes emerges as the main protagonist; and almost all of my Grimes novels are set early in his career.
Both isfdb and wikipedia give a pretty good in-universe chronological order, and of course it's pretty easy to figure out publication order as well.
Any advice on how to go about reading this series? Is it important to read the Calver stories first? Anything I should be aware of that can't be deduced from isfdb?
Thanks for any help,
Tony