The Stoker-Kirk drive is the main propulsion for the Vandian class ship Enterprise III in The Wheel.
Newer ships (such as the Guantanamo Bay) sport the vastly superior Sagan-Armstrong power plant, but speed and distance don't cut the mustard when you need to travel across half the galactic arm.
The Enterprise III has the weapons needed to blast any enemy from kingdom come.
The only remaining Stoker-Kirk example is in the Jupiter Yard, mothballed centuries before. It's so slow and outdated, it's not worth the effort (or expense) to bring it back online.
That's what's so shocking when the Enterprise III shows up again close enough to reach Scotty's Star.
Then the real fun can begin.
Here's a short section for you to read.
The locations of known red stars had been pulled up by the thousands. Giants were discounted, due to their massive energy output. From Levi's observations on Se'Yan't, high-energy stars were out as a homeworld for the devils. It was that narrow habitable zone of the red dwarfs that interested them.
It made sense, in a way. Red dwarfs were some of the longest lived stars in the universe. This race must be immensely old to have manipulated humanity for its entire history.
After performing tests on the remains of the firedevil to determine chemical composition and radiation tolerances, three possible positions were pinpointed as the most plausible locations to check. The Enterprise was now parked in orbit over an unnamed world circling Scotty's Star. The sun, although very small in actual size, consumed the horizon. The planet was well within the coronal flare range, and the ship's shielding was being battered by violent solar activity. God help whatever lived on the surface of that world.
From Chapter 66, The Wheel