I have 23,000 miles on V80 blend (80% wvo/20% RUG) that is only heated with a coolant heat exchanger. Last week I started on V90. The engine has 423,000 miles.

I had nearly 10,000 miles on completely unheated, unblended wvo on my 1981 300SD, but it was taken out by a deer. It was running great when it died.

My wife had 9000 miles, then I switched her over to diesel for winter. She's now back on V90. Her injectors were coked and I just cleaned them yesterday. All my cars suffer from injector coking, but so far, it has not caused any issues- they just look bad.

__________________
1984 300Sd 210k

Former cars:
1984 300D 445k (!!) (Strider) Original (and not rebuilt) engine and transmission. Currently running on V80 ( 80% vegetable oil, 20% petroleum products). Actually not, taking a WVO break.
1993 300d 2.5 275k. Current 120/day commuter
1981 300SD 188k (Hans) Killed by a deer