I found Terror's Reach to be a gripping read which constantly reminded me of Alistair Maclean.
The isolated group of people in a lonely location, the mysterious forces at work, strong brutal characters, damsels in distress, the constantly shifting balance of power are all trademarks of Maclean's finest work and Bale uses them all in abundance.
Joe Clayton is of course something of a cliché, but without the cliché his character would not work as well. He is forthright, strong, ingenious and most of all moralistic - with the usual troubled past to give him depth.
Priya, Liam and Turner are the best of the bad guys, with Priya being the standout of the three. Among the uber-rich Nasenko and Robert Fenton are equally dislikeable and Fenton's son Oliver is a fantastic addition to the cast.
There are some excellent twists to the plot which weaves and wends its way back and forth constantly providing new scenarios as different protagonists gain superiority before the final battle royale. The prose is tight with clever insinuations as to motive and desire.
To sum up Terror's Reach I would have to say that it is an excellent adventure written in a new, yet familiar way.