From looking at your other thread you appear to have a 61db attenuation which means that your line length is rather long. Since you're getting a 2500 ish sync rate that is about right for your line. Some people get a little more, others don't
One thing I will note is that my parents' line had a 58db attenuation and when using a Netgear DG834GT (piece of crap had to be replaced sharpish) and another Solwise router, the line sync would settle to around 3000kbps, so 2.5mbit BRAS profile. After replacing it with a Belkin 7633 it's now syncing at almost 4000kbps all the time.
For what it's worth, they're about 4km from the exchange in a straight line with a 5.5km line length. Sync rate is around 3900kbps so that's hitting the 3mbit BRAS profile.
