it is difficult to answer in essence to two different questions.
about 150 ms - or rather still 100 ms. Initially it was stated that 150, then 100 ms. So to understand the long-distance vMotion:
In vSphere 4.1, vMotion was supported only when the latency between the source and destination ESXi/ESX hosts was less than 5 ms RTT. Metro vMotion was introduced in vSphere 5.0: the maximum supported round trip time latency between two hosts was extended 10ms with vSphere Enterprise Plus license.
In vSphere 6, long-distance vMotion will be possible with up to 100 ms RTT between two hosts, allowing cross-continental migrations.