Any N600 has 300mbps on the 2.4 band and the 5ghz band. That is 300 for send and receive so max real throughput is 150 mbps; in the same room as the router you might get 100 or very optimistcally 115-120. Adding a couple walls in its path and that will quickly drop to half.
If being able to achieve the 125 mbps transfer is most important then get one of the routers I listed earlier.
EDITED:
If you were choosing the Netgear now I would say to get the TPLINK one as Netgears N600 degraded in quality with each version.