To add my .02:
I run my car on 85% wvo/ 15% kero. Lately I have been adding 100% wvo to my drum - I only use the kero to thin it enough to filter when I get fatty oil.

So far (3000 miles), the car runs great. I do not dewater, but I filter well and get good oil.

I am going to install an aluminum heat exchanger since I believe heated WVO burns more completely and if I encounter any fat in my wvo, it is less likely to clog my filters. The exchanger costs about $75 and uses waste heat from the engine. Otherwise, the entire car is unmodified.

__________________
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