The reason, as stated before (and this also came up in the Aromazap thread recently) is that stainless steel discolors over time, and people might then also think something is wrong with their Solo. Coating the bowl seemed more professional and high-quality to Arizer.
It sounds like this was a case of shoddy manufacturing to me. Tons of vaporizer manufacturers use ceramic coated heating elements and yet I've never heard of a flaking issue with say, a 7th Floor product. I realize that it's not exactly the same since a bowl and an element are not the same thing, but the principles seem comparable.
The LB and the Solo are very different products. Personally the Solo doesn't seem attractive to me because I feel a portable should be a simple device, but if you want something that feels closer to a desktop vape in a portable form factor, it might be for you. Also provided it's still going on, you can't beat Randy's price.