No. Tesla's own numbers are obviously more reliable than insideevs.com guesses. Here is what Tesla reported to shareholders regarding its first three months of Model S deliveries:
"In Q3, we produced almost 350 and delivered over 250 Model S sedans to our customers, all while maintaining very high build quality levels."
Technically, Tesla did deliver a handful of cars 8 days before the quarter began, so we don't have data on EXACTLY the first three months' sales and production. But these numbers are not more than 8 days off.
Bottom line: At this early stage, the Model 3 ramp is NOT any faster than the Model S and Model X ramps. It is in fact eerily similar to the prior two ramps, despite being designed for ease of production. It is early, we can hope for faster ramping in future periods. But it's not happening so far.
Here's a link to Tesla's report:
Tesla Motors, Inc. Third Quarter 2012 Shareholder Letter