No other way of getting a definite answer, but we can give you a very close idea of what your IP profile is if you go to the link below, download a file from it and tell us the average/optimal consistent speed you get in kb/s.
http://fuller.zen.co.uk/test
Test results from the 10mb file downloads
7:30am - Avg 110kbps/Fast 150kbps
8:30pm - Avg 45kbps/Fast 75kbps
Cheers