West Coast Imaging "DOES" offer B&W services in Chromira. In fact, I just talked to them yesterday about doing 5 of my large format B&W negatives in Chromira instead of Piezography. I had a B&W done 2 weeks ago on a lightjet printer from Photo Craft Imaging and it had incredible detail.
As an experiment, I took 3 of the same photo to work (a piezography print, an epson 9600 print, and a lightjet print) and virtually everyone chose the lightjet print. I'm seriously considering doing all my B&W this way. Once I get back my prints from West Coast Imaging, I'll decide whether to go for the Chromira or the Lightjet, but it will definitely be one of them.