With so many similarities, is it possible to judge one better than the other? Yup. Twenty Four Hours was the better book for a couple of reasons. One, the main baddie was a bit more believable. It's possible that there might be a smart criminal out there who would develop the perfect (yet simple) plan for kidnap-for-ransom. In contrast, the baddie in Just One Look knew all these pressure point techniques and had this sociopathic personally that made him seem unrealistic. Two, Just One Look was more of a mystery/thriller, with the mystery element being a bit convoluted and implausible. Some people may like this element, but I thought the plot of Twenty Four Hours was more clean, with the book ending once the protagonists were no longer in peril.
Overall, these are both good thrillers and worth looking at if you are studying how to create tension in your writing.