For a UK game, an ILL18 player will stay or double in some plus count cases, while a BS player will hit :
16 vs 10, 12 vs 3, 12 vs 2, 9 vs 2, 9 vs 7, 16 vs 9.

In some minus count cases, an ILL18 player will hit while a BS player will stay:
13 vs 2, 12 vs 4, 12 vs 5, 12 vs 6, 13 vs 3.

There will be more similar cases if surrender is available.

So a BS player will eat more high cards in plus count and leave more low to the ILL18 player in minus count.