The technically differences are missing something and are inaccurate. The claim is that there is no advantage to PPPoA over PPPoE but this is not true. PPPoA has less overhead over PPPoE http://forums.whirlpool.net.au/wiki/?tag=ADSL_Theory_PPP

In my opinion, from the smart customers POV PPPoA is nearly always a better choice then PPPoE. There are a few configs were PPPoE is better but not many. From ISP's POV, PPPoE might be better but you are not the ISP. Some of the issues mentioned in the technical information are also irrelevant since you can't use more then one login with one connection with TMnet as far as I'm aware.