Dave X10 is an expert on X10 cameras, he has a bunch, and I have none, but my two cents is:
Unless you have lights at the gate, you probably do not want X10 unless it is the expensive Sentinel and even that does not have particularly good sensitivity.
The inexpensive "Night Watch" camera which is X10s low cost, low-light, B&W, camera needs supplemental lighting. Non of the X10 cameras are particularly sensitive to IR and none have IR transmitters. Also, X10 does not provide any specs, but they do offer a battery pack for any camera. X10 claims AA batteries will last "up to four hours" so they ain't exactly efficient (they use CMOS pick-ups, if that tells you anything). Maybe Dave x10 has a better opinion, but my two cents is to look else where because of your power and sensitivity requirements.