does your internet link feel zippywithout any slowness, or is there any slowness from time to time?

In reply to a post by Kiggs:

Just interested, is it possible if you're syncing above 15MBit with ADSL2+ you could actually see a reduction in peak time speeds when moving to a relatively busy FTTC cab? I know Openreach guarantee 15Mbit throughput at busy times.

It's an aim to reach, not guarantee. Also it's only 15Mbit if you're on a 40Mbit service. For 80Mbit users it's 30Mbit prioritisation rate.

As people have said, it's very rare but theoretically possible to have a congested link from the cab to the exchange, but most visible congestion happens at the exchange and its backhaul.