Personally I've never had any problems with the AOL software itself and the BT Voyager is rattling along at a steady 3.5megs + (my line only supports 4.5!).
Using
speedtest.net and trying different servers to test from the download rate (and the upload) ramps up steadily to the max. available with very little deviation. However using the Netgear it runs in 'fits and starts'

upto a max. of well short of 1meg (usually aroud 6-800kbps)
As for the line attenuation using the Voyager it reports:
Local.....31 Remote.....20
SNR margin db:
Local...13.5 Remote...12
Line rate 5120kbps down 544 up and data 4567kbps down 448.
These last figure are reasonably close to what I'm getting with the Voyager for 2 miles from the exchange.
My gut feeling is the ADSL routers goosed as its receiving and transmitting speeds are so asthmatic