That v3.1 Model you have in your cart from Sculpteo has all four buttons. If you compare using the single button models with the same individual parts, with parts selected separately at Shapeways:
WSF
Sculteo $72
Shapeways $84; 15% more
WSF Polished
Sculpteo $80
Shapeways $90; 12% more
If you compare the 4 button model with parts selected separately at Shapeways:
WSF
Sculpteo $79
Shapeways $94; 20% more
WSD Polished
Sculpteo $90
Shapeways $102; 13% more
If you compare all Alumide parts selected separately with a WSF Internal:
Sculpteo $93
Shapeways $109 at; 17% more.
Oh sure get all fancy with the percentages....