IMO, the Amuse Vestito kit is overdone to hell, especially with the large amount of knock off's floating around. Price seems kinda low also. It's pretty good for the real kit, but I'd make sure it was legit before forking over that much loot.
If you want the Nismo Kit, go for the Nismo kit. Z1 Motorsports sells the conversion kit without the rear wing for around $3,700+Shipping.