I have a soma non-highrise stem on my soma doublecross. It does a fine job of connecting the bars to the steerer tube. I mean, what else can I say about a stem? It hasn't failed, it's not hideous, and it doesn't spray tear gas at me.
I just got one of their 7 degree rise ones recently and some of the threads on the top bolt stripped. It's not fatal but when I switched bars and re-threaded the top bolt on, about a 1/4 way in it got really tight and the threads inside the stem (not on the bolt) looked stripped. I just kept going and it re-threaded itself but it made me a little leary of their stems.