Since I received few private messages asking about Skiman Bravo, I'll post my further comments here. Over the 17/18 season I have used it extensively in both in the EU and the US (using 110/220V transformer). Have not been disappointed.
If the skis are maintained (daily grinding if skiing on ice, or weekly grinding otherwise), then one pass per side is enough. I follow with couple of manual passes with diamond stone. I found it saves the edge (less is ground with one pass), compared to manual filing.
The belts go fast. One belt lasts no more than 3-4 times sharpening (12-16 passes). I do not use the "original belts" since it would be too expensive, just order belts for stainless steel using the original measurements (372x10mm if anyone is interested). Thus, the cost per belt is roughly 0.5-0.8 Euro/USD. From experience I get better results with blue (zirconia based) belts than with brown (aluminum oxide) belts, but the former are less durable of the two.