try to list out this

what OS? touch screen? QWERTY? 3G? Wifi? Free GPS? or what?

Free GPS, is one of the best feature for me.
By now, Nokia got provide free navigation OVI Map for certain model.
And, Symbian can support Garmin, android cant. (Garmin map is the most detail and updated Malaysia map, and can be download for FREE & ANY TIME)
Touch screen is the latest trend. and more suit for movie, web browsing, play games, due to it BIG and NICE screen.
For the detaisl above, i would suggest u go for Nokia X6 8GB. 8++ (ori).

vivaz not that cheap, the price near to 1000 (Ori).
Vivaz is resistive screen, but X6 is CAPACITIVE screen. For all round, capacitive is better than resistive much more, in term of responsiveness. Resistive need some kind of pressure, like finger nail and so on. But capacitve screen just need a SIMPLY TOUCH. very comfortable. This is why last time IPHONE will grab lots of touch screen markeet share, due to capacitve screen.
However, Vivaz got higher MP camera and video record. But X6 with 5.0 MP carl zeis lens, is more than enough. Unless u very focus on HD recording.
Vivaz did not have Free Ovi Map. But i noe on web got haked version, the problem is dunno whether the hacked version can still update map, voice guidance, ..... for life time.
Capacitive screen?  OVI Map? Video recording? determine ur self.

below 8++, then Nokia X6.
below 99+, then Vivaz
Slightly above 1000, then HTC wildfire

2 different worlds phone can suits u

gaming & nice screen but worse video record/playback, camera is bad too- wildfire[android]
gps, hd recording - vivaz[symbian]
free gps & nice screen - x6[symbian]

SE seems no longer provide update for vivaz, they gave up symbian market~

if not mistaken, vivaz around 9++, right?
if like that, i prefer go for others. IMO, not worth.
i will rather go for X6, C6-01,HTC wildfire.

not sure with AP price, bcos the differences might huge different.
IMO, C6-01 is really a good phone, but the biggest drawbac is Fixed focus camera.
If u dont mind, then really a good phone with a very good budget

tats mean when u take photo, there is no auto focus, directly take the pic

what problems u heard?
nothing perfect in this world.
mega pixel just determine the size of photo.. Higher mega pixel do not mean better photo.

audio problem i might agree ermmm...
the loudspeaker abit soft

recording got wad problem?
continuos autofocus HD video recording 

battery problem, lots of other SE models users oso face such problem...[saw from forums & frens]
my fren[w595 user] said, for a sudden, her hp battery drains out faster than usual eventhough she just sent a few sms...!
sometimes she can't charge over the 50% mark...no matter how longer it charges...it still stucked @ 50%

desire hd and milestone 2, which one is better?