Nikon SB - 600 or Nissin Di - 662???

I've been thinking of getting a flash since i get my Baby Nikon D90.

So after months of struggling finally i got 2 selection on my hand.
It's either the Nikon SB - 600 or Nissin Di - 662.

Nikon SB 600

Electronic Construction	Automatic Insulated Gate Bipolar Transistor (IGBT) and series circuitry
Flash Exposure Control	TTL automatic control with Nikon F5, F100, F80, F75, and FM3A; Manual control; i-TTL Balanced Fill-Flash with Nikon D2X, D2Hs, D70, F6; D-TTL Balanced Fill-Flash with Nikon D1, D2 series or D100
Guide Number	Approx. 30/98 (at 35mm setting) at ISO 100
Flash Coverage	Automatic 24 to 85mm zoom; 14mm with built-in wide flash adapter
Recycling Time	Approx. 3.5 sec. with AA Alkaline manganese batteries, 4 sec. with AA lithium batteries
Number of Flashes	Approx. 200 (Alkaline) 400 (Lithium)
Weight (without battery, memory card or body cap)	Approx. 10.6 oz.
Other Features	Modeling flash, LCD panel illumination, Color filter set
Dimensions	Approx. 68.0 x 123.5 x 90mm (2.7 x 4.8 x 3.5 in.)
Power Requirements	Four AA-size batteries
Supplied Accessories (may differ by country or area)	Speedlight Stand AS-19, Soft Case SS-600
Film Speed Range in TTL auto flash mode	ISO 25 to 1,000

Nissin Di 662

Specifications

• Usable camera : CANON digital camera, NIKON digital camera
• Guide Number : 44m, 145ft. (ISO 100), 62m, 205ft. (ISO 200)
• Variable power : 6 levels : Full - 1/2 - 1/4 - 1/8 - 1/16 - 1/32 powers
• Flash exposure control : E-TTL and E-TTL II for Canon cameras / i-TTL for Nikon cameras
• Power source : 4X LR6 or equivalent Mi-MH, lithium, oxyride batteries
• Recycling time : 0.2 -4.7 sec., with fresh alkaline batteries / 0.2 -4 sec., with Ni-MH batteries
• Energy saving system : 5 minutes to stand-by mode, 30 minutes to shut down
• Number of flashes : 200-1500 flashes by fresh alkaline batteries
• Illumination angle : Digital lens : 16mm (14mm with wide angle diffuser)
• by zooming reflector :
  to - 18 - 24 - 35 - 47 - 57 - 70mm
  Traditional lens : 28mm (20mm with wide angle diffuser)
  to - 28 - 35 - 50 - 70 - 85 - 105mm
• Turning head : 90?? upward, 90?? to left, 180?? to right
• Slave mode :
  Slave sync : with respect to the digital pre-flash system
  Power level : same as the variable power above
• AF Assist light : Infrared LED for distance of 0.7 to 6 meter.
• Color temperature : 5,600K (same as daylight)
• Flash duration : 1/800sec. to 1/20,000sec.
• Camera contact : Hotshoe only (not compatible with the traditional hotshoe system)
• Accessories included : Shoe stand, pouch
• Dimensions : 77(W) x 130(D) x103(H) mm / 30(W) x 51(D) x 40(H) inches
• Weight : 315g (without battery) / 11oz

After doing much research, i find out that the Nikon should be way better then the Nissin. There's only one problem the pricing problem, the price between this 2 is quite a lot. Sigh.