I grew up with Ace doubles like this, and loved them. This book is one that I missed, so even decades later I'm glad to have an opportunity to read it.

Both novels are decently written. Each starts out as interesting adventure stories, but get more than a bit preachy and pompous towards the end. That was a general tendency of novels of that era (1964), as I recall. In addition, the plot kind of fizzles out towards the end of both. So, 3 stars for the pair ... an interesting and enjoyable read, but don't expect too much from them.

One fascinating feature of "I Want the Stars" is the naming of two of the alien species ... "Borg" and "Horta". Fans of 'Star Trek' will recognize both those names! Given the copyright of this novel, I have to think that the Star Trek writers "borrowed" these names. Nothing wrong with that, really, but it is interesting. ( )