Tubular Front Control Arms

I beleive the reason most don't is due to strengh issues.

The stock A-arms, while ugly and heavy as sin...are strong! Tubular ones with a coil spring have a greater change of failure. When you hit a bump on a coil-over setup, the force goes from the wheel, through the spindle and up into the strut's spring, bypassing the control arm. SO they can make it lighter and not as strong.

With a coil spring on the arm, the force of the bump has to go through the a-arms. A lot of aftermarket companies make parts for race cars, with the general assumption that most people will inspect their parts more frequently.

Making a a-arm with a spring perch invites people to toss a set on their stock daily driver and put 100K of normal street driving on them....which is a scary thought without a lot of testing.