It's essentially sci fi with a Western vibe to it, much like Firefly...but, it's not Firefly. Maybe more like 50s era sci fi mixed in, but without the cheesy visuals and special effects? Eh. Check it out as you said, make your own choice. I loved the storyline and the game, myself.
I should say, the Spacer's Choice Edition version upped the level cap to 99. I don't think there's any way in hell you could ever get that high, unless you want to grind everything in sight on every planet, and even then it would be a stretch. I got to level 42 or so; the previous game cap was level 30. But I'm a completionist; I did 99% of the side quests and both of the DLCs in full.
The game has a lot of tongue-in-cheek comedy, but the storyline is rather bleak and serious. The voiceovers are nice, and the characters that ally with you can grow as characters, to an extent. It's pretty awesome from start to finish.