NOT EVEN CLOSE!!!
Exhibit A: My time trial car
Exhibit B: My CMC car
So, I have one of each. The S197 is a FAR superior chassis in terms of pure stiffness, compared to a gutted and caged SN95 with subframe connectors. Up front, the McStruts have better geometry than the modified Macs on the SN. Out back, the situation is even more extreme. The S197 has a fairly fluid 3-link plus Panhard, where the SN95 has the Quadrabind suspension, guaranteed to misbehave under ANY cornering condition. The CMC car has a fair bit of work done to the engine: Cobra intake, injectors, computer, roller rockers, "E" cam, shorty headers, and the "good" heads. It makes 260RWHP on the nose, with a crappy (rolling) hot idle. The 4.6L 3V makes almost exactly that number as well, bone stock. The S197 has a pretty good stock 5-speed (3650), where the SN95 has the self-grenading T5. Even with a late (03-04) suspension update (front arms, rear axle) the SN95 STILL has a substantially narrower track-width than the S197.
All in all, the S197 is the superior chassis. A few select mods here and there and the S197 will compare favorably with anything short of an SLA/TA setup on an SN95, with more (cheaper/easier) power, more torque, and FAR more potential.