Metro-North's Comet Vs are for West-of-Hudson operation (Hoboken to Port Jervis or Spring Valley). There have been cars operating out of Hoboken wearing Metro-North logos for decades, these being Comet IA, Comet IIB and Comet IIS most commonly (the IIS being the same as the "Shoreliner I" that operates out of Grand Central). There also used to be an RDC shuttle that operated between Suffern and Port Jervis in the 1980s. All trains are operated by NJ Transit. You won't ever see Comet Vs in GCT unless the proposed Tappan Zee rail bridge is built...
The WMATA-like trains belong to MARTA, which operates in Atlanta, Georgia. (Yes, those stripes look very NJT-ish, don't they...? Acronym stands for "Metropolitan Atlanta Rapid Transit Authority." Their website:
www.itsmarta.com)
The PL42AC is 69 feet 10 inches long. Weight is a whopping 144 tons. Horsepower is 4200. Tractive effort is 69,975 lbs. (Source
here.)
The pictures weren't taken from a train. They were taken
at the Alstom facility in Hornell, NY.