oldsinner- I think you're wrong! Do you actually have any personal experience with this specific system?? I've had two different vehicles that I've used this way and
never had any problems with anything concerning the tank, lines etc. Plus, I know a couple other guys who use the same system without problems. Per the heaters (???), they aren't necessary. It gets to 0* and single digits often here in Missouri, and like I said, if you cut it with diesel or kerosene, it works just fine. I also mentioned that I filter it with a 5 micron filter, which is twice the filtering that car filters use, and IF there's any "animal fat", as you mention, it settles to the bottom of the cubies before I ever filter it, and gets discarded before it can ever get to the filtering process. Personally, I think people who go overboard with de-watering devices (water also settles-just don't put it through your filters, or smarter yet, don't get oil that people allow water to be mixed into), slingers, yada, yada, are making a mountain out of a mole hill. I really don't understand the "bio-diesel" mentality of over-priced machines and additives when vegetable oil is all it needs, (except somebody is making a ton selling them).
I've never had a problem with this system. If
you choose to use greasecar.com's (or any other brand) system, that's your prerogative. But until you've tried this system, you really don't know what you're talking about. About every thousand miles or so, I dump some Lucas fuel injector cleaner in the tank, and it works fine. But my oil is so clean before I put it in the tank, it looks like it just came out of a new, unused bottle of Wesson.
I think you worry too much. Maybe someone has told you stories to get you to use their system or something. This system works great, and a lot of people I know also like it. If you don't want to buy the car, don't. But don't bad-mouth it if you've never tried it or personally had a problem from it. By doing that, you're screwing with my ability to sell the car because someone might believe what you're only assuming.