I took the weights off of my Skorpion to see how much difference they make, and the answer is A LOT! I wouldn't like to think what it would be like riding a long distance without them.
The plastic coating on the Skorpion weights has a bad habit of peeling off and the weights then go rusty. This had happened on mine when I bought it, so I replaced them with 'universal' stainless weights from Hein Gericke. Various other suppliers (M&P, Buster's, etc) sell universal weights, so there's plenty of choice. Just make sure that you get ones for steel bars, as the ones for alloy bars suit a narrower inside diameter.
Personally I would avoid alloy or carbon fibre weights; as the purpose of 'weights' is to add weight to damp vibration, what's the point in fitting light ones?
Norman
http://www.mzskorpion.net