Which of the following statements about FIDO XT is incorrect?

The statement regarding FIDO XT's basic mode being the most sensitive for employment on vapor samples of a suspicious package is not accurate. While the FIDO XT device is capable of detecting explosives by analyzing vapor samples, its effectiveness can significantly vary based on the mode it operates in. The basic mode might not always provide the most sensitivity compared to advanced settings which may be specifically optimized for different detection scenarios, including various types of samples. Understanding the operational modes of the device is crucial for maximizing its detection capabilities in real-world applications.

In contrast, the other statements reflect true characteristics of the FIDO XT. It indeed is effective in detecting vapor samples, is designed to function effectively under various weather conditions, and is known for boasting a fast response time, all of which contribute to its utility in counter-improvised explosive device operations.