There is no information about what the nuts and bolts of the Sky package will offer.
We don't know if Sky will have a heavy interleave that can be dropped when asked. Infinity DLM can turn the interleave off to fastpath.
We don't know if Sky will set the default noise margin to a higher value than BT which could drop the synch speeds of the sub 40 meg lines.
We don't know how the supplied router performs and knowing Sky you most likely will have to use that one with no choice of using another one that may have features you want to use.
So it is a wait and see situation especially as BT will most likely be offering their new 80/20 package in the next couple fo weeks.