"Sweep in Peace" downloaded to my kindle and I'm not ashamed to say, I read it immediately! And it was good.
You definitely need to read "Clean Sweep" first. The whole thing (especially the emotional plot) works better if you do.
That said, this is a great series. The world building is strong. Fans of George and Jack (from Ilona Andrews' "The Edge" series) have a real treat in store. No spoilers, no spoilers!
I thought this had a tougher emotional plot than "Clean Sweep" which was more a light romantic adventure - albeit in a fantastic alternate reality.
I'm just really happy, and "Sweep in Peace" goes on my re-read shelf.