Pretty similar, and quite possibly came out of the same factory! I don't think the SGS was around when I bought mine (or if it was I didn't know about it) so when I became aware of it I went and had a look at it just out of interest. My conclusion then was that the SGS perhaps wasn't quite as well built - the welding wasn't as neat, for example - but that functionally they would be very similar. If I were to buy again now I'd probably still go for the MM simply because it's a known quantity, but I have no reason to suspect that the SGS isn't every bit as good.

Yesterday I was in my local Indy spares shop and they are selling the Polco 3 tonne trolley jack at £90 its another clone of the SGS / MM family but has the side plates stiffened by top edge fold over edges and has a grease nipple on the main pivot bar.
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I guess all the Chinese engineering firms must be watching each other and copying.
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Kind regards from Fred.
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