Well there are quite a few differences between the two and I will do my best to address them.
Landmark you get higher quality carpet,40# LP tanks,Cherry wood interior,Hydraulic landing gear which I think is awesome,power shoreline reel,place for (2) batteries, battery cut-off switch,large 30" convection microwave,sealed stove burners,mirror/tinted windows,"G" rated Goodyear tires,soft touch ceiling,fluorecent lights,Euro hidden hinges,pocket doors for bathroom.
These are just the highlights from my comparison spreadsheet I put together a while back when we were looking to upgrade.
Good luck,
Mark