GM Europe claimed different figures than GM North America. While the C7 Z06 officially hits 60 mph in 2.95s with the auto tranny (American-spec; apparently it's not politically correct to use "tranny" anymore; most publications and sellers now substitute "trans."), it is also said to do 62 mph in 3.4-3.7s (depending on whether it is equipped with the Z07 package or not).
As for that 185-195mph top speed range, it is complicated. In the real world it should be as fast without the Z07 package, if not faster than, the C6 ZR1. Considering that 60-127 mph in 8.0 seconds flat with the 2.95s 0-60 and 10.95s quarter-mile drag times on stock street tires could enable as much of a 0.65s reduction in 0-60 with tire changes, a 10.6@129 slip is achievable on street slicks.
2.3/60/(60/127)x127+0.65 = 10.95 1/4-mile and 2.95s 0-60
Based on GM's 0-60mph time, we could estimate that the C7Z does 0-100km/h in 3.1s with the optimistic 1-foot rollout. In traditional testing, it's 3.4s (as Cadillac Europe says) with the Z07 package and 3.7s without it.
3.1 divided by 10.5 = 295 km/h (183 mph) top speed
3.4 divided by 10.8 = 315 km/h (196 mph) top speed
3.7 divided by 11.1 = 333 km/h (207 mph) top speed
The C6 ZR1 and C7 Z06 have roughly the same performance and personality as the SLR McLaren of the mid-2000s. All have 600+hp supercharged V8s, two of them have automatics (well, at least the Z06 has it as an option), all have 205+mph claimed and tested top speeds, and all are front-engine rear-wheel drive beasts.