Jet Pac on the Commodore VIC-20 is pretty much the same as the classic ZX Spectrum version. It even has ‘colour clash’ like the original…
Shoot the aliens; collect and drop the parts of your ship; then collect and drop the fuel, before taking off. The game moves a bit more quickly, which makes it more difficult than the original, and the graphics are a bit chunkier (although nowhere hear as chunky as the BBC Micro version), but otherwise it is the same great Ultimate game as seen on the Spectrum.
Jet Pac does have limited lasting appeal, but then again: it is squeezed into only 8K of RAM. The basic game, though, is excellent – it’s a retro-gaming classic!
More: Jet Pac on Wikipedia