Ya if you are looking for longer flight time the SP140 is the better option over the X4 as it’s just more efficient.
If you are just looking for 1/2 flights the 2.2kwh battery might be the best for you. That brings the ready to fly Sp140 price out of the box to $6700. And extra batteries are $995.
So that might be the better option for you. It is also lighter weight of course.
Might work on a lower cost Sp140 pack that use lower capacity cells but the whole batteries cost would come down quite a bit. Right now we use the highest quality cells we can find but that also makes the cost higher of course.