What is fast 3G?

Simulated throttling, which Lighthouse uses by default, uses a simulation of a page load, based on the data observed in the initial unthrottled load . This approach makes it both very fast and deterministic.

The average speed of 3G connections is 3 megabits per second (Mbps), which was 30 times faster than 2G average speed of 100 kilobits per second (or 0.1 Mbps). Some 3G connections could achieve speeds of 7Mbps.

The technical limit of a 3G connection is 384Kb/s , however o2 have recently admitted that personal customers are only getting a 128Kb/s connection, with business customers being the lucky ones to be upgraded to 384Kb/s connections.