Comparison between Nike Mercurial Vapor VIII FG and SG pro

FG 

• Lighter
• Fore foot section is more flexible
• Twin studs at the back 
• A bit cheaper
• 'Quicker release from ground'

• Not suitable on turf
• Twin studs at the back might break
• 'Studs are molded'
• Only bladed studs

SG Pro

• Interchangeable studs (screw-in)
• More traction on SG
• Mixture of FG molded bladed studs as well as aluminium SG studs.
• 'Suitable for any condition' (HG, SG, FG)
• More support at fore foot section

• Heavier
• Stiffer fore foot
• A bit more expensive