[JKnight]

First off, what's your intended usage of the car? Track, street, fairground cruiser? This will help determine if the lower-end units will work for you.

Is the Speedtech unit significantly more costly than the Heidts?

If you're doing any significant performance driving, I would be doing everything I could up to and including reprioritizing my budget to make the Speedtech subframe a possibility.

I know Heidts has come a long way with some of their products, but using drop spindles is a non-starter for me.