I bought a 110B via eBay, back when Dean was selling that way. The workmanship of the conversion was fine, and the camera came in a nice kit with a case and a CD-ROM with information on the conversion.
In the end, I didn't bond with it. Mine came with the original-issue 127 Ysarex, and for my taste it didn't cover adequately for 4x5 at the wider apertures I needed for hand-held use. Also, I found the thing clunky and awkward to handle. The devil is in the details on these things - a big part of how comfortable it is to hold one of these to your face is determined by the exact profile of the back, and this varies from one shop to another.
A 4x5 Crown is bigger and heavier, and I don't find that especially comfortable to work with either, though I'm finding that a 3.25x4.25 Crown that I had fixed up recently is enough smaller and lighter to make a real difference. IMO all of these are on the edge of what is practical for hand-held use, and because there's such a large element of personal taste involved, it's hard to give general advice or to know where the line between practical and impractical will fall for you.
FWIW, another shop that does these is Alpenhause.
If a 3 1/4
crown or Speed fits you, you can get film from Freestyle, and sheet film holders on e-bay