You'll have to define "worth it"; that varies from person to person. You should also define your goals: what, specifically, do you want to change aerodynamically or in the handling?
Then you need to gather some data. Are the lowering springs for the front stiffer than the stock springs? How will that change the balance with the stock rear springs? What are the natural frequencies of your suspension, front and rear, now? You can find out very easily with just your smartphone:
Will lowering your vehicle decrease drag? Will it decrease drag enough to show up as an improvement in fuel economy? Unfortunately this is harder to answer, as you can't really test ride heights without an adjustable (air) suspension. Based on everything I've read (which is a lot), cars
usually show a drag decrease with lowering but not
always; there's no guarantee yours will, and none of us here can say one way or the other.
For what it's worth, if I was starting out with a new car or SUV I wouldn't bother lowering it unless I was changing the suspension for some other reason. But if you do, an interesting experiment might be to identify a 200 mile or so freeway loop, run it and record fuel economy; immediately swap the springs and then fill up and run the same loop again at the same speed. If there's a difference in drag it
might show up in a test like that.