I don't... actualy know what is and what isn't a good record...
I thought what to respond to this all day, and still don't know what a solid response might be...
I guess I can advertise show a leaderboard for the game. You can also submit your runs there.
Here's the link: https://www.speedrun.com/thunder_jumper_demo
Yeah... Not that I hacked into the game's code, most of the stuff in Grouch's video was a little exxagerated. More specifically, I just replaced (for example) the files for the level 1 with different level files, to load each level one by one. When I tried that on the 10th level, I got into this secret level. No "hacking into the game's code" to find that, it wasn't even that complicated.
