There were no Alusil E34s. Even the first year of the E38 in the USA had a Nikasil block. I wouldn't trust a BMW Nikasil V8 as far as I could throw it, I don't care how many miles are on it. Time-bomb and hot-potato are descriptions that come to mind. Heck a chipped 525i is just as fast, gets much better fuel economy, is easier to work on, and has no longevity issues. And if you're talking about an automatic, most likely no one ever changed the ATF since the dealers and the manual were both confused as to whether or not it had lifetime-fill fluid. They did NOT. And if it doesn't have AST, keep looking!