Phone runs pretty smooth with the second generation snapdragon processor, it might take some getting used to opening up the dual screens though. Before actually playing around with the phone though I was scared it was just going to be a dual screen Zio but its a pretty impressive device.
I had the Sanyo M-1 phone a number of years ago. The phone was WAY ahead of it's time then. It was a solid phone. The camera on the phone was 2nd to none. I took a 2 MP picture that won a photography award at a county fair. It was an outdoor shot but no one knew it was taken with a camera phone. LOL.
Successful? Sure. But they've been doing mostly low-end phones for the past few years, so I would say that the definition of "successful" is different than it would be for a high-end smartphone like this. This is new territory for them (at least in recent years... they did make successful Palm OS smartphones ages ago.)