Just kind of wanted to know if one is "better" than the other.

Failing that, what which one is more stable to run on modern hardware.

(Windows 10, Ryzen 5 5600x, Radeon RX 6900 XT)

Second Contact runs better.
This one is more nostalgia ;)

This one has weird FMV sequences that have some charm for the time they were developed. Second Contact has awful FMV sequences.

This one has a very unique graphical appearance because of the technology chosen and the compromise of not using textures. Second Contact replicates the aesthetic using textures.

So my answer is actually "why not both" :D