I GM'ed this for both high- and low-tier tables.
When I first read the description for Truth Keepers I was apprehensive. "A terrorist attack on Absalom Station takes a crew of Starfinders to the heart of the Veskarium." I was concerned that this would be yet another ploy by everyone's Public Enemy Number One, a certain white-furred ysoki whose paw prints could, so far, be found over most scenarios in Season 2.
So I was pleasantly surprised to find Truth Keepers was its own self-contained story. Better yet, it was a self-contained story with a tremendous amount of heart!
The scenario's introduction is a paradox--it is both unorthodox, yet classical. You find yourself at a bar, rather than the briefing rooms most scenarios start out in. Players seemed to enjoy being given the opportunity to imagine their characters' normal after-work personas, gravitating toward things they think their characters would do or enjoy after a long day of, well, Starfindering.
That peace (and also a window) is shattered by the call to adventure, which most characters quickly seize upon diving into a combat to support one of three charming NPCs, each with unique abilities and personalities (one of my groups especially loved Toast, who shouted words of encouragement from behind her makeshift barricade).
The scenario doesn't lose any of its personality once the mission gets underway, with Venture-Captain Naiaj trusting the PCs to undertake a quasi-legal operation in the Veskarium under the supervision of an old friend. The investigation is both lightweight and varied, and no two groups I've run the table for have selected the same investigative routes twice. There's a lot of fun to be had with each lead, and players are genuinely charmed by the variety of characters and personalities they encounter during their mission.
The final act of the scenario is, perhaps, the weakest, because it involves the most combat. In most cases, enemies have no tactics, leaving it up to the GM to divine how they prioritize targets or engage threats. Likewise, PCs who do not adequately explore their environments may end up fighting a battle on two-fronts, a scenario that nearly killed one of the PCs at my table (he was left with 0 hit points and 0 resolve at the end of the mission). Even then, players were thrilled by the foes they encountered (particularly one well-timed callback) and generally enjoyed themselves.
The reason why I give this scenario four stars instead of five, however, is that there were several important details that were lost during editing and not put back before the scenario went to print. One encounter gives varying information on how many enemies are present. One encounter omits mechanics for an ally's abilities. One map is oriented incorrectly, confusing the PCs about their exploration choices.
Overall, I would say that Natalie Kertzner & John Curtin put together an impressive repeatable that I will probably not tire of running anytime soon. The scenario's clever writing, fun characters, and lightweight mechanics made it an instant favorite, and I hope to continue to see scenarios of this quality in the future.