There is a lot to like in this book - not least it's near 100% compatibility with the Doctor Who game. It's easy on the eye, fun to read and provides a time-hopping premise that is, if anything, more suited to roleplaying than it's sister game due to it's provision of the ARC organisation for PCs to be part of. The selection and descriptions of evolutionary eras, and the creatures that goes along with them is the major highlight for me - but the whole game is pretty slick and professional. My only disappointment was that they've gone overboard in the use of bookmarks to the point that there are multiple entrees on pages in too many cases. As such, it's pretty hard to navigate as a pdf.
[4 of 5 Stars!]