I've never owned one, but I've met around half a dozen as patients at the various vets I work for, and they are uniformly all attitude. Some are friendly initially but freak out when handled, and some are just bad-tempered from the get-go. Coworkers of mine have similar experiences.

They seem to be smart, independant, full of personality, and very strong-willed, meaning that where an average cat may grumble and hiss a little when you trim its nails, the Bengals I've met will go into full-blown explosive rage. Welding gloves and cat-nabbers are a big help in getting them out of the cage...

They are absolutely gorgeous, and if they ever develop some that are truly tame, I'd think about one...they seem to have neat personality quirks. As they are right now, you couldn't pay me to keep one...I like cats I can handle without shedding blood. :-P

Also, I'm sure there are some friendly ones...they seem to inspire a rabidly devoted following among those that own them. They're just not good in a professional environment where I meet them. :-P

Oh, and lastly...there seems to be some mythos of them as giant wildcat types...I had one client tell me that his 2lb kitten would be a 30lb adult (as he'd been informed by the breeder)...it maxed out around 9lbs fully grown (and every last ounce was seething fighting muscle).