Smooth steels are the best way to go. A steel does nothing more than re-align an edge. This is assuming you already have an edge thet was sharpened using a fine stone. Why go through the work of using a fine stone, just to put a rough (grooved) steel on it? It doesn't make much sense does it. Also, I worked in a pig plant last summer and I had 4 knives and a steel on my hip all day. It was a slightly grooved steel. The steel I have at home is completely smooth, and I find that it does a better job. Read John Juranich's book on sharpening for more detail on what I told you.
By the way, MY 100th post!!!
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