The underlying infraastructure will not change, however teh termination at te exchange may do - from one line card to another. So, your speed should not change drastically. There might be a minor up or down change caused by the change of termination - if you understand termination impedances which can vary slightly you would understand why.
Do not worry about contention - it is unlikely to have any effect especially as teh exchange has fibre back haul.
And who says you will not get FTTC? There are exchanges only slightly larger than yours where it has been rolled out - Rhynie is one example.
M H C
taurus excreta cerebrum vincit