The similarity is whether the new game is integrated into the old one. The choice is up to the manufacturer. When I bought Forza 5, my garage from Forza 4 was accessible. Did I get a whole new game with new tracks, new physics, new cars, new modifications, etc..? Of course. Did I explore more of a different career mode? Yes. Could I - for nostalgia or preference - choose to use one of old cars for a new track? Why not? It was still mine, but now I don't have to load the old game, the game developer can use my new stats as usage to report to its stockholders, I get to use the new physics on new tracks with new AI in a new world, but with something I obtained in a previous generation. The point being is that with a choice - YOU chose to use old stuff, in a new environment. Why should that ever stop? Ever update an operating system, and lose all of your old files? Or were you able back them up/import/migrate, or otherwise make compatible? If you've been around networking/computers a lot, you may recall Windows XP migrating to other versions, but still allowing "classic view" for individuals who were not ready to learn a new OS. Some did, some didn't. But the choice was on the user, so if you liked it - great, if you didn't - great. Win/win. I'm also using a combination of Year 2/3 stuff. If I could, I'd use all 3 years. There was a clean break from Year 1 and 2 (to a major extent), and I did NOT like that - enough that I refuse to purchase any more Destiny related products if this continues (I'm currently playing on my youngest son's license). So I respond with my wallet (however insignificant that may be).