Re: Speed - what speed
However reality is that most times during the day I struggle to get 1Mb/s; video streaming is often so blighted with pauses I give up in disgust.
If you can currently connect at 17Mb/s at any time then you already have a pretty good connection. The fact you can't saturate that connection 24/7 is probably a separate issue to that being discussed here. It's possible that your exchange is congested but that's pretty unusual. BTor are fairly good at managing SVLAN/VP capacity. What does your exchange status say if you put it in here.
I'd be inclined to blame your ISP or possibly you are using a wifi connection and interference from your neighbours is limiting throughput during peak hours.