well C901 is better.. because it has xenon flash while C903 only has LED flash..since u not stated GPS.. then go for C901..
if u want GPS.. can go for C903..

c903 dont have front camera for 3G ..but c901 got

I want HP with the best camera around Rm 1 000 budget. Don't care about the brand and other function. I just want the best camera

Suggestion please 

Is this the best among all SE Hp ?

so what??
C901 is old phone

well.. let see..

Pros of G900 - nice 5mp camera , touchscreen[if u like] , has WLAN @ WiFi , has camera touch focus[focus by touch at the screen while taking pic] , well... G900 is a smartphone .. and using Symbian UIQ as OS , has secondary videocall camera

Cons of G900 - have 3G but not 3.5G[no HSDPA,HSUPA] , no GPS , has slow processor.. but not too slow..

Pros of C903 - has accelerometer , has HSDPA,HSUPA , has built in GPS with A-GPS... ,

Cons of C903 - not touchscreen[if u like] , camera still on par with C902 , no WLAN @ WiFi , no secondary videocall camera , not a smartphone
well.. for me G900 is better than C903 in terms of function, camera , wifi.. etc..

but for me .. i dont like G900 because.. it is already outdated, no GPS... and I will buy other phone than this...

well .. i wanna know.. how much budget do you have..

C903 is worse than G900..

so G900 is the best choice if you dont want GPS[GPS in C903 is no good..]

well.. let see..

Pros of G900 - nice 5mp camera , touchscreen[if u like] , has WLAN @ WiFi , has camera touch focus[focus by touch at the screen while taking pic] , well... G900 is a smartphone .. and using Symbian UIQ as OS , has secondary videocall camera

Cons of G900 - have 3G but not 3.5G[no HSDPA,HSUPA] , no GPS , has slow processor.. but not too slow..

Pros of C903 - has accelerometer , has HSDPA,HSUPA , has built in GPS with A-GPS... ,

Cons of C903 - not touchscreen[if u like] , camera still on par with C902 , no WLAN @ WiFi , no secondary videocall camera , not a smartphone
well.. for me G900 is better than C903 in terms of function, camera , wifi.. etc..

but for me .. i dont like G900 because.. it is already outdated, no GPS... and I will buy other phone than this...

well .. i wanna know.. how much budget do you have..

C903 is worse than G900..

so G900 is the best choice if you dont want GPS[GPS in C903 is no good..]

well Sony phone only available and only can be use[network] at Japan only
I can sugest you SE Elm , SE W705 , SE G705 , SE Yari
Both is look like same..

SE Elm - candybar
SE Hazel - slide

SE Hazel slightly better in terms of
- camera , videocam ... slightly better
- also has secondary camera, while SE Elm not
- 16 M color than 256k color in Elm [well you wont notice this]
SE Hazel is better choice.. but still dont know the price yet..So.. I cant say it is the best in terms of price:performance...

SE Elm is RM 600.. and it is the best phone for the phone that in range RM 600