It's Mario's first NES adventure!
Being the first game that was packaged the the American NES system, it is a classic from day one!
My only real comment on this game is, THIS GAME IS HARD!!! I have beaten every other Mario game easily, just never this game. I tried the Japanese version thinking it may have been a little easier, it wasn't. Since I got the other Super Mario games for Famicom, I thought it would be nice to have the first one as well. All the tricks and glitches from the American release work on this version as well.
I usually have some trouble with controlling Mario because he slides a little when stopping, the jumping is a little challenging when it comes to jumping forward, than trying to stop yourself and move back. I am just used to the controls of Super Mario 3.
All in all, Super Mario Bros. is a great game and will forever remain one the greatest classics of all time and should be in every Nintendo fan's collection. Grab it while you can!