I just finished the first book in the series and have grabbed up the second (there are 10 books and counting, as well as a number of short stories). I plain found this book to be hilarious; ok, my sense of humor may differ a bit from yours, but the situations that the main character and friends get involved in are exciting, dangerous, and at times, ridiculous. Really, who hired these people? Let's just say that they have a very specific skill set that qualifies them for the work . . . .
So for a fun, quick read with the possibility to continue the journey through time and history appeals to you, I highly recommend this series!