Next thing you know we'll be like banknote collectors, looking for ascending, descending, radar, solids, zeroes, and Chinese fortune numbers. 1234567, 7654321, 1234321, 3333333, 123400, 100000, 8888888, 4444444.
A matched pair is going to worth more at resale time, fired or unfired. You have to sell both of them, though. "One of a matched pair" won't help, unless you're Bill Hickock's grandkids.
A pair of Taurus revolvers? Maybe in 44 Special, an extra hundred bucks. Otherwise, not so much. Pair of Colt Pythons? Name your price.
The semiautos pictured above? The time spent selecting them at the counter was worth it. How much is an unknown, but time will tell.