Guns retailed under the Joseph Lang name tend to reflect their position in the London gun trade at the time of manufacture rather than a grade or model range. Originally Lang was little more than a 2nd hand dealer but as time went on he produced some lovely finished guns made within the London trade. Some of these had most unusual and interesting features like the Phillips trigger exhibited by the more expensive gun. These reflect a special order rather than a company design policy.
As time went by they largely used actions easily recognisable as Webley Patent Screw-grips, mainly back action sidelocks but a few bar actions and boxlocks thrown in.
Then, after the amalgamations that eventually produced AG&L, the name was used to market cheaper boxlocks.
Both these guns are back actions using the Thomas Perkes lockwork and either the Webley Screw Grip bolting or something very similar. The cheaper once is 28" x 2 1/2", border engraved, uncased with poorer wood without drop-points. The more expensive is fully engraved, showing some colour, 30" x 2 3/4" (probably reproofed), much better wood with very nice O&L case. Also a rare and interesting trigger mechanism.
Price reflects all the above plus barrel condition (not specified) and what they bought it in at or the demands of the consignment seller.