The Car & Driver test car is a RWD model, with the MRC. The MT car is an AWD model, with standard shocks. Cadillac is not positioning AWD in the new Vs as a performance enhancer, but rather as a traction enhancer for those who live with severe weather conditions on a frequent basis. The lack of MRC mirrors the old ATS Premium conundrum: MRC with RWD, no MRC for AWD. The Mercedes and the Audi need the AWD for performance, because FWD can't really handle that level of power, while RWD can. Only recently are BMW and MB adding AWD to their over-powered sport sedans, to help them get 600+ hp to the ground. The M2 and the most recent M3 and M4 are RWD only, like the ATS-V, and the CT4-V probably drives better with RWD and MRC accordingly, except on ice and snow. It's certainly lighter.
The CT4 is quite obviously a reworked ATS, with a slightly longer body and an upgraded interior. I think the extra length may be in the rear, as the trunk is a bit larger, and the opening is larger and more accommodating to large items. The interior is still cramped, unless the front seats are moved forward, but the "competition" is equally cramped. The BMW 3 Series, the MB C Class, and the Audi A4 are all a bit roomier, but a fair amount more expensive. As far as performance, let's see how the turbo lag is. The 2.7 off-boost should have more shove than any 2 liter off-boost, even with AWD. I recently saw an article about the effect of turbo-lag on real world performance, and how the 5-60 performance is more telling than the 0-60 performance, especially when they pre-load the turbos. I bet the CT4-V RWD with 2.7 may run away from the competition with the rolling start. Time will tell. They talked about how the BMW X2 M35i with AWD does 0-60 in 4.6, but 5-60 in 6.4, barely quicker than a Honda minivan (6.6 sec)! Apparently, it takes awhile for the turbos to spool, the transmission to find the right gear, and the AWD to send the power where it needs to go. As a comparison, the Mustang GT does 0-60 in the same 4.6, but 5-60 in a much quicker 5.0 seconds. No contest.
In any event, this might have been called a CT4- V Sport in past nomenclature, like the BMW M-Sport, so I think it's a pretty good effort for the money. It's too bad the rear end is kind of ugly, and the rear upper fenders are so busy. It probably has all of the performance anyone can really use on the street. It just lacks bragging rights.