I surprised myself by finishing the book. The first page put me off it with the description of Murdock, and it never really got much better. The whole cold war, anti USSR tone was overdone, f'r example the assumption that the only way the Russians could be technologically advanced would be with the help of alien technology rankled; and the speed that Murdoch decided to be a teamplayer because he didn't like the other side seemed like just so much propaganda. I know it was written in the 50s, and may have been less remarkable then, but to a reader now it jars.
It was fast paced, but there was no real substance to it. I won't be reading the rest of the series. In fact I was hoping they'd all get shot down in a ball of fire when they got back to Earth.