Around 2 hours 17 minutes to beat. The game crashes at 7-4, so I considered that the completion point. I also lost some footage of 7-1, but stay tuned til the end and I show the full 7-1, including the hidden 1-up in the extra footage. I show 2 warps and explain the strats that I used. This may be the only video of this specific version, as I could find no information on it online and no videos.
This game is a hack of the original Super Mario Bros, and thus I use the continue code included in the manual of the OG game. Since its in the manual I consider it legit to use and not a cheat.
Unsuccessful continues are edited out, but successful continues are shown, including lives lost.
I have 2 or 3 other versions of this hack. There is one that has only 4 worlds. Not sure if I have that one, or what the differences are between the other versions. Maybe I will try them at some point too.