Assuming I am not misunderstanding you, you're talking about the WiFi speeds from the access point device that's connected direct to the modem which has N300 WiFi only, right?
The point I was making was that N300 is a 300Mb theoretical maximum which you never get in the real world. The range is short so it will degrade with distance, but you'll also see significant interference from other WiFi networks around you, as well as things like cordless telephones, microwave ovens, baby monitors, and all kinds of other things that are commonly found in your home and other houses around you that share the same 2.4GHz frequencies.
Just to give you an idea. If I sit at the other edge of my living room to my router and connect to the 2.4GHz band, not even a ~50Mb connection will carry wirelessly at full speed. I see about 35-40Mb. This then drops as I move into other rooms until I get to the conservatory at the other end of the house where I am at 2-5Mb but if I connect to 5GHz I am still at, or very close to full speed.
Or if I have completely misunderstood the question and my sleep deprivation is finally catching up with me - Appologies.