I don't think he is a horrible person. He's just not that smart.
Spoken from a person that probably knows more about Flex and has met Flex. Everybody else has just conjectures and hearsay.
I think he's arrogant and yes selfish, I think the arrogant part is a act. As far as being selfish, most bodybuilders are. Flex had stated that he did not feel bad taking food out of a another bodybuilder's mouth, which is why he did the Ironman and the Arnold Classic. I don't think he was smart with his money.
And he did state that he had to be on test because his body was producing so little, this was on his video that chronicled his comeback in 2002.
As far as Flex's ride now, he is working for MD, and he does have a salary, and we don't know if MD gave him the car or he bought it. Plus he still probably has connections to the music business as well (hell, he'd make a better trainer to 50 than Stan Mcquay).
I've talked with people who have met Flex, and some have said he was cool, others have said he was asswipe, I guess it depends on his demeanor that day, and the other person as well. Because if some of the people on getbig act the same way in real life, a lot of people would be assholes to them as well.