In reply to Cameron94: Some additional info. All 3 of these new screws have been designed with a a new drill that helps with starting but also gives a ware indicator so you can tell how far you can sharpen them.
The teeth are designed so that you don't loose length when you do sharpen them. the Laser Ice has an alloy hanger which reduces weight compared to the old Laser, about 135g and about £39. The Laser Speed is very similar but with a handle, similar weight, about 140g and about £48.00 The Laser Speed Light is the clever one as its aluminium tube with steel teeth, 100g and about £54.00. As you can see I managed to get hold of a catalogue!