I picked one up in Austria years ago, mostly as a souvenier, but tried it a couple of times. They are like all clay pipes, they get very hot during a smoke, so you need to be careful what parts you handle. The smoke was cool enough, but lacked the flavor that good briar imparts and the bowl, made of a porcellan like material is fairly fragile. they are a sit and smoke type item rather than something you might travel with.
All things being equal, briar is still hard to beat.