well...
The dyed fuel is "off-road" fuel. The dyed fuel seems to plug fuel filters faster than regular fuel. On occasion I have been forced to use the red stuff, and found mileage to drop by 3-4 mpg over the standard diesel, and performance does not seem to be on par. The exhaust also "smells" different.
There is also a fine, $500 I believe (somebody correct me if I am wrong), for getting caught using it by the DNR. Around here, they spot check at farm sales and write tickets on the spot for offenders.
As far as damage goes, there have been people using it for years in their trucks with no apparent damage. I am not sure how the VP44 will handle it though.