Sorry mate but I think you have this account a bit mixed up. The Axxess uncapped account only gets throttled from 8am-8pm Monday to Friday and the rest of the time it runs at full speed according to what ADSL line you have. If you max it out downloading on a 4MB line you can expect to get well over 700GB a month. The Imagine accounts run at only 384Kb the whole time meaning you pay a similar amount to download a little over 100GB if you leave it on 24/7. You can't compare these packages there just so different.
Maybe he is not so mixed up as you think.
You are comparing throughtput on a 384k line to throughput on a 4 Mb line - not a fair comparison.
The real comparison therefore is:
Imagine uncapped 4 Mb line - R2499 (theoretically giving 1.1 TB of data bandwidth)
Axxess uncapped throttled 4 Mb line - R2699 (theoretically giving 700 GB of data bandwidth)
That is quite a difference in my opinion.