All the best GT cars of consequence today, including Corvettes, Ferraris etc., and virtually all race cars with independent front suspension have short upper control arms fitted above longer lower control arms (SLA) instead of MacPherson Struts. All Mustangs* from 1979 to current utilize MacPherson struts front suspension.  The reason is not for superior handling, but to afford the automaker a fast and relatively inexpensive way to produce the car.  While struts work fine driving in a straight line or with light cornering load, inherent geometric deficiency prohibits full realizations of a tires performance, especially under high lateral load.

*65-73 Mustangs and 74-78 Mustang IIs were produced with SLA suspension, the latter being a Pinto chassis. Utilizing Struts here would be considered a downgrade, however the geometric layout of these cars are not conducive to truly high performance use on today’s high grip tire technology and they are highly compromised in a variety of other ways such as rigidity, camber gain, anti-dive, roll center stability, and large tire fitment without an excessive scrub radius.

SLA vs Strut on Wikipedia:
"SLA or double wishbone suspension provides the engineer more free parameters than some other types do. It is fairly easy to work out the effect of moving each joint, so the kinematics of the suspension can be tuned easily and wheel motion can be optimized. It is also easy to work out the loads that different parts will be subjected to which allows more optimized lightweight parts to be designed. They also provide increasing negative camber gain all the way to full jounce travel, unlike the MacPherson strut, which provides negative camber gain only at the beginning of jounce travel and then reverses into positive camber gain at high jounce amounts.

Although struts are a popular choice, due to its simplicity and low manufacturing cost, the design has a few disadvantages in the quality of ride and the handling of the car.  Geometric analysis shows it cannot allow vertical movement of the wheel without some degree of either camber angle change, sideways movement, or both.  It is not generally considered to give as good handling as a double wishbone or multi-link suspension, because it allows the engineers less freedom to choose camber change and roll center.

A strut is rigid mounted to the spindle and cornering and braking loads are usually pressed against the hydraulic piston and cylinder of the damper, degrading performance and longevity.  Additionally, it tends to transmit noise and vibration from the road directly into the body shell, giving higher noise levels and a "harsh" feeling to the ride compared with double wishbones, requiring manufacturers to add extra noise reduction or cancellation and isolation mechanisms.

SLA systems have a shock absorber that can be lighter, less complicated, and being independent of braking and cornering loads suffer no such compromises and therefore deliver superior performance.  More importantly, the roll center is stabilized.  In a strut system as the body rises and falls, as during brake dive, or rises under acceleration, the roll center migrates usually double the change in ride height. With a proper SLA system this change is minimal as ride height changes. This contributes to a far more stable chassis balance as the car transitions through the 5 zones of a corner, braking, turn in, mid float, power application, and exit. It is especially beneficial on rough or undulating courses and through esses.

The next big advantage to SLA systems is camber gain, which is the change in applied tire camber as the wheel travels up into the wheel well as the suspension is compressed. With struts the camber curve is minimal, or even regressive, actually losing camber as the wheel travels up in bump motion. So as the body rolls in a corner, compressing the outboard suspension the loaded tire loses applied camber to the road surface, reducing tire contact, and wearing the outside shoulder. To compensate, high static camber settings are needed, 3 4 or 5 degrees, to compensate for tire deflection and camber loss form body roll. But these high negative camber settings are detrimental to performance due to reduced tire foot print under braking, and inconsistent tire contact patch area during transition into and out of a corner. It also results in high shoulder wear. Most front strut cars wear out the tires shoulders, both inside and out while leaving at least a third of the tread in the center of the tire.  Griggs Racing SLA systems have aggressive camber curves designed for current generation performance tires. Static camber on race tracks seldom exceeds 2 degrees. Properly aligned, tires last much longer without the excessive shoulder wear, and performance is more than significantly improved due to the near always flat tire contact patch.

The larger and sticker the tire and the more down force applied, the more brake and cornering load in the front end. Therefore, more reason to use an SLA. The changeover to an SLA system is truly an amazing improvement to the front end of any Strut equipped car no matter how it is driven.