If they can figure out where their local cabinet is, then you can get a good idea http://www.buckconsult.co.uk/fttx/BT8cProfilesVDSL2.jpg shows what you could expect. The line to look at is the 8c one.I think that graph is slightly optimistic as
a) it doesn't take into account crosstalk
b) it assumes the full 8.5Mhz bandwidth whereas OR's FTTC on 8c is actually limited to just over 7mhz - the difference could be over 15Mbps (although on lines long enough for it to matter probably a bit less).
WWWombat posted a link somewhere to a document containing graphs which took account of crosstalk.
The graph also appears to start at 90Mb.
As BT's FTTC starts at 40Mb, the speeds achievable at 5000ft (1524m) would surely be much less than 35Mb.
I achieved 32/33Mb when FTTC was first installed on my 800m or so connection from the cabinet, against an estimated 14.6Mb.
After around a month, my speeds had dropped to below 15Mb (following a line fault that left me with no phone or broadband for 4 days).
Following many engineer visits, speed is currently hovering around 20Mb & my ISP tell me that as it is still exceeding my original estimate, they cannot report any faults to BT, despite a continued loss of 12-13Mb or so.
FWIW, having access to an unlocked modem & graphing tools, I see that some days I get absolutely F.A. from the higher frequency VDSL2 downstream D2 band, any downstream being delivered only via the lower frequency ADSL2+ downstream D1 band.
Edited by Bald_Eagle1 (Thu 20-Oct-11 11:44:05)