Has anyone played these, and are the extras on them worth getting. They sound cool to me, but I would like other people's opinion before I spend the money.

They are exactly the same with some slightly better graphics and modes. They all have Mario Bros. on them as an add-on. They are well worth it, in my opinion. Definitely not a waste.

I have one threw three. These games are great if you want to play Super Mario on the go.

I will probably have to get these sometime soon.

It is nice to be able to play these games on the go. All I need to get now is Super Mario World for the GBA.

For changes, SMA1 (SMB2) has a ton of life-up items tossed around, a new boss, and the "Yoshi Challenge" where you need to find Yoshi eggs and bring them to the end of the stage without dying. SMA2 (SMW) doesn't have much - you can play as SMB2 Luigi and there are 5 dragon coins on each level, plus it's easier to get colored yoshis. SMA3 (SMW2) has 6 all-new levels at the end of the game, and SMA4 (SMB3) has e-reader support, allowing for some minor level changes and a bunch of all-new level. Most of the interesting changes requires Japanese-imported cards, though.