Yeah there is no comparison, I am on BT which is probably worse than sky FTTC, and its still light and day difference from VM.
If I saturate the upload, then I get slight jitter

on VM all hell breaks loose and its in the mid 100s (if not already in the mid 100s). If I download no affect on latency at all, and if I download on VM, whatever speed VM is maxing out at even if say a few mbit/sec again all hell breaks loose on latency. Doesnt matter if its 9am or 9pm I will still get max throughput, snappy browsing and good streaming.
The 2am thing dont worry about it, its not looking a constant issue so not really a problem. eg. my line yesterday had a burst of 3000 crc errors at 1am, it wasnt enough to even show on the tbb graph and since then I have had 250 errors in 18+ hours after it which is pretty much nothing.