For a caliper to fail catastrophically would put the supplier in a BIG legal mess is how i look at it Ben , my steering rack is from Roughtrax and no complaints a few year down the line despite my oversized tyres and willful attempts to break things .
I'm inclined to think 80 calipers also fit the 90 series but i can't be sure , was it Andycruiserlomas that did the swap ?