Since I got Galaxy W & Galaxy S II at the moment, decide to did a Small Review Comparison on it.

• Galaxy W Stock player not support playback of 720p MKV file. Anyway it is playable via MX Video Player Pro via SW / SW Fast mode. (Preferable SW Fast Mode). The performance is solid and smooth actually even though it is only software decode by MX Video Player Pro.
  
• No Automatic Brightness Support.
  
• No haptic feedback. I don't think it not support just it never do in the software part.
  
• Even though Galaxy W is only single core 1.4Ghz, I find it performance quite similar with Galaxy S II dual core 1.2Ghz. You hardly seen a huge different in performance wise in general usage, off course they is different in gaming wise.
  
• Galaxy W only use LCD and no pure black, but I find the color wise is much more accurate and nature. Galaxy S II is too vivid and fake color reproduction. You can notice a huge color issue on Galaxy S II when you turn on the camera and see the screen comparing actual object.
  
• Galaxy W is quite stable in overall, I never face any hanging issue yet include photo taken. Galaxy S II sometimes will give you hanging issue during photo taking & on/off few times the WiFi/Hotspot.
  
• Galaxy W internal RAM is too little which only 351MB in total, this generally often facing RAM full occupied issue. Galaxy S II wise is more than enough, as it got gorgeous 0.91GB of RAM.
  

If u have the money why not going for the S Plus?
Bigger internal mem 8/16gb, AMOLED + Corning Glass somemore.. Other spec the same as W 

go for S plus for sure! If you got $

Well i tested my friend SGII, its screen does have better black, but then again W screen is no slouch either, way better than ACE & Y screen for sure..

If its me and i have the money i dont mind forgoing the AMOLED screen for a dual core cpu HP like R, my friend in SG is using it and he has no complaints
The thing that isnt that good is that in Msia its only AP right? hmmmm

Why do you compare single core to dual core. 512MB RAM to 1GB RAM. If you're ok with AP set, and got the budget, of course choose R la. But mind you. R is just 4.2" SLCD, not AMOLED
You know why they have better blacks? AMOLED/SUPER AMOLED/SUPER AMOLED HD/Anything that got 'AMOLED' shuts down the pixel when it's required to display black while LCD backlight will still be on all the time even if it's not displaying any colour.