New Vivitar DF-583, any thoughts?

Hey,

I have a Nikon D7000. I was trying to find a SB-600 for it, and ran into one for $180. Turns out they're out of course, so they talked me into a Vivitar DF-538 as a substitute for $189. I can't find any reviews on it online.

Anyone have any thoughts on these? I'm not familiar with Vivitar products at all, and this is my first TTL flash. Should I send it back and just continue my search for a SB-600? They said it has about the features of the SB-700 or more. I'm more worried about how well the basics perform, not so much the extras. I want iTTL, and accurate adjust-ability. I tend to work everything manually anyway. I plan on mounting it on a tripod and using umbrellas. It'll be here next week.

Thanks!