Slower fuel-efficient jump drive implications?

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What the implications of a slower but more fuel-efficient jump drive?

I am considering trying to rework the Islands clusters as being like CJ Cherryh's Union Alliance setting in tech. This would mean that jump drive takes 1 month external time for a 1 parsec jump, but uses much less fuel, such that a ship can jump 4-5 times without refueling while still having a lot of cargo capability. Internal time is 1 week, but because of sensory distortion people have to spend it sedated to avoid mental damage.

If the Islands developed this kind of drive and used it extensively, what would happen when the Imperium contacted them? Would the Imperium find the new drive useful for trade or military purposes, or just say "how quaint" and keep using the usual fuelhog jumpdrive?