Here's a few more examples:
The one I just had made,
Kentucky,
Moss, and
Georgetown.
I'm sure they're all nice, and I particularly like the look of the Georgetown model. However, I own the one in the first link and it works just fine. I prefer to hold the bowl in my hand as I build lather and that model allows me to do so.
The basic premise is to allow the shaver to either create and keep warm lather in the inner bowl, or in the case of the Moss version, to keep the loaded brush warm by placing it in a bowl surrounded by warm water. it is quite effective and I thoroughly enjoy my warm-lather shaves. Some of the members own more than one of the ones listed, but I haven't seen a bad review yet.
The only caveat I can think of is that of pre-warming the scuttle before use. By warming the ceramic prior to loading it with hot water you can have warm lather longer. Otherwise, the scuttle works like a heat-sink and cools your water off rather quickly.
You won't necessarily bypass using the sink by having one, but I've saved water by only using enough to heat and fill the thing for my shaves. If I can get a matching bowl for mine I plan to use the water inside the scuttle for rinsing my face before discarding it. It's not hot by that time, but it's still warm enough for a rinse and there's plenty in there (and it keeps the sink available for my wife!).
I'm sure plenty of others will weigh in on this soon.
- Mark (S-4-C)