is that 8Mb on the same scale as the 2.59Mbps or what would 8Mb equate to (approximately)
No, the 8 Meg is the connection (sync) speed from exchange to router, the 2.59 Meg is the throughput over wireless.
8 Meg Sync = about 6.6 Meg throughput over Ethernet = 'how long is a piece of string' over wireless.
What are his router stats?
1999: Freeserve 48K Dial-Up => 2005: Wanadoo 1 Meg BB => 2007: Orange 2 Meg BB => 2008: Orange 8 Meg LLU => 2010: Orange 16 Meg LLU => 2011: Orange 20 Meg WBC