6P

How did this compare to the first three books in the series? Which is your favourite?

Sand Storm – 4.17
Map of Bones - 4.21
Black Order – 4.58

All the books come very close to the same rating and I think we are all in agreement as to why they aren't higher. I think in spite of it having the lowest overall rating that I liked Sand Storm the best. The best book he's ever done is one called Excavation a standalone.

My personal ratings were:
Sandstorm 3.75
Map of Bones 3.75
Black Order 4
The Judas Strain 3.5

I noted that I'd considered putting Map of Bone at 4 but I had issues with the library, Gray's father and Nonna so I was unhappy with the ending. So, overall this one has been my least favorite but they've all been in the mid-3 to 4 range.

Sandstorm - 4
Map of Bones - 4
Black Order - 5
Judas Strain - 3.5

This was definitely my least favorite.

Sandstorm - 4
Map of Bones - 5
Black Order - 5

Sandstorm is my favourite of the series (4.5★s), probably because of its sci-fi plot; I have to admit to a penchant for sci-fi. (And hence the ending of the current book lifting my final score).
The other three are all on a par at 4★s each - who knows how much higher they'd all be if Rollins just picked up his pace, though.