Can the SB Audience Bianco-15OB350 be used successfully in a RIPOL system?

I can't think of any reason why not. Looks like a perfectly suited driver for a ripole or even better a double ripole or w-frame.
It does not have a very high mass cone, it has a low enough resonance frequency, Rms is low enough, BL is decently high, Xmax is more than enough, Qts not too low but not too high either. I would have liked to see a sturdier frame but considering the low price it's o.k. In other words, a great find. I'd say go for it.
 
Yeah, these are not true open baffles? Doesn't the compression chamber change the room interaction?

I like the idea of small powerful subwoofers. And If you can fit a 15" RiPole, you can probably fit 2x 12" RiPoles for stereo.. 🙂