Don't get too carried away. I believe those were performance "P" dual motor prototypes, and the when Elon said the production will be faster, he meant the P versions.
I would expect the normal dual motor versions to be only slightly faster as they are with the TMS 70 and 70d.
I expect We will see something like this:
TM3 60: 5.8s
TM3 60D: 5.5s
TM3 80D: 4.9s
TM3 P80D: 3.9s
I agree mostly; however, I expect Tesla will attempt to beat the 2018 BMW 3 series in 0-60 times.
Therefore, I think your estimates are a bit too high.
My estimates: 0-60 times
current 328i: 5.8 sec
-> T MS 70: 5.5 sec
-> T M3 60: 5.6 sec
current 328i xDrive: 5.7 sec
-> T MS 70D: 5.2 sec
-> T M 3 60D: 5.3 sec
current 340i xDrive: 4.6 sec
-> T M S 90D: 4.2 sec
-> T M 3 80D: 4.3 sec
current BMW M3: 3.9 sec
-> T M S P90D: 3.1 sec
-> T M 3 P80D: 3.6 sec
-> T M S P90D Ludcirous: 2.8 sec
-> T M 3 P80D Ludicrous: 3.3 sec
Just speculation of course
The Model 3 might be even quicker still.
I expect the Model S will see an upgrade in battery packs until the production of the Model 3 starts (80 and 100) and this will shave some more time off the aforementioned 0-60 times for the Model S.
That said, I agree 5-60 times are a better indicator of a car's driving performance than 0-60 times.
This truly is the reason electric cars are so much fun to drive.
I think the Chevrolet Bolt will be a lot of fun and the Model 3 even more so obviously.