I would "hope" that all whiteboxes are now the version 2 spec as it would be very difficult to correctly manage the distribution of version 1 and version 2 boxes depending on the connection profile.
The use of the whitebox connected as per samknows instructions will not impact the internal network - the 100Mb/s connection will only limit the transfer speed to and from the internet (which is far from ideal!).
BT Infinity 2 - IP profile 77 / 20 - super fast!
Previously BE Unlimited - 21,000 Download 1,200 Upload but then moved house - 6,500 Down, 1Mb/s up - gutted!
Ex <n>ildram , been to SKY MAX - 15,225 Download