I don't know exactly what he means by 3rd generation, but $400 would be a good price for any 625 around HERE.
It requires clips for normal operation with 45ACP; load, fire, extract. Full- (6 shot), half- (3 shot, WW I style), and third- (two shot, not much use but you can box ammo in pairs with them) moon clips are readily available.
Most of the family of .45ACP revolvers can be loaded with and will fire .45ACP without clips. Then you have to poke the empties out with a pencil or pluck them out with fingernail or the rim of a shell. I have heard of some chambered a little too deep for reliable ignition with loose ACPs but they can't be common.
Or you can shoot .45 Auto Rim; same case dimensions as .45ACP but with a big thick rim. Big enough to extract, as thick as the .45ACP rim plus the thickness of the clip. Remington still makes the brass, PMC has loaded ammo fairly recently.