School me on drop spindles...
Drop spindles, while crazy expensive, would be the best way to lower the front and retain handling vs. dialing down the torsion bars. Lowering via the torsion bars changes the spring rate, making for a mushier front end. Also closes the distance between bump stops.
This isn't true.
Lowering your car with the torsion bar adjusters does not change the spring rate. In fact, it has NO effect on your spring rate whatsoever. Torsion bars are linear springs, and nothing you can do to them short of taking a torch to them will change your spring rate.
If you look at how the LCA and torsion bar adjusters work, you'll see that what happens when you turn the torsion bar adjusting bolt is that the angle between the LCA and the torsion bar socket changes. That lowers the car by changing the angle of the LCA with respect to the frame. The weight applied to the torsion bar by the car doesn't change, it just lowers the point at which the weight is applied.
Drop spindles are completely and totally unnecessary if you increase the size of your torsion bars. The only problem that comes about with lowering the car using the torsion bar adjusters is that it reduces the amount of available travel your suspension has. If you have stock torsion bars, that's a problem because you need all of that travel. That's why stock suspension feels worse when you lower the car with the horribly weak stock torsion bars, its because you're bottoming the suspension while driving. Or maybe even sitting on the bump stops.
But, if you have larger torsion bars than stock (1" or more) you won't use all of that travel anyway. The 1.12" bars on my Duster have a spring rate of 300 lb/in, which is almost 3x the rate of stock V8 bars. Which means I only need about 1/3 of the travel I needed with stock torsion bars. Probably less, because the larger bars "react" faster to suspension inputs.
The drop spindles also introduce some bump steer. Not enough to cause problems for street driven cars, but they do add some bump steer. They also eliminate the benefit of going to 18" rims to clear the outer tie rod. Because they "lower" the outer tie rod end with respect to the suspension, 18's no longer clear the outer tie rod. So you're limited to ~5.6" of backspace again, just like 17's or smaller.
Drop spindles are not the only "right" way to lower one of our cars. You're better off buying the right size torsion bars and lowering the car with the adjusters. You'll not only pick up the lower center of gravity, you won't add bump steer, and you'll handle better without the horrible stock torsion bars. For about the same price.
I ran my Challenger with Magnumforce's 2" drop spindles for years. I swapped them out when I realized I could get the same overall ride height without them. I kept everything else the same, including the 1.12" torsion bars I'd had on the car the entire time. There was NO change whatsoever in the quality of the ride of the car. None. And I haven't bottomed out the suspension even once, in about 10k miles of driving daily.