Correct. They are indeed opposing type, also know as 4 Pot callipers..
Anyways, just went and picked up a county front axles housing... and they are noticeably bigger pistons in the county housing when compared to standard front disco callipers.. The pistons in the county callipers almost come right to the edge of the calliper (ie top or bottom of the calliper as it is mounted when you are looking at it) and when compared to the disco stuff, MASSIVE difference. You can just see the disco pistons in the calliper, so no doubt that just callipers alone would make a huge improvement.

