hmm. so between both of this which one is better.anyone tried both? all i need is speed!

ok will try the official want and then galnet.

there are two official version.

miui.us (US dev)
miui android (UK dev)

and then, Galnet v1 and MCG v6/7.

so i'm right if I say MIUI is fragmented 

scrolling between homescreen doesn't lag, but isn't smooth. low frame per second, to be more precise.

camera i think quite ok. i haven't test 720p recording yet. maybe later.

ahh, i see. so what version are you now? i'm looking over the galnet version rather than those us build one.  kinda poison juga to me somehow oh ya, is the titanium backup is working if i restore all the apps back from froyo to miui? seriously bro, tonight is the first time i ever use titanium backup, never tried it before this although i got this phone for like 7 months already. so noob. lolz

If battery juice is important. don't flash cm7/miui.

I however do not need 24/7 data switched on. I am contempt with green power battery saver app. it gives me almost whole day of use

The CM site says, 'CyanogenMod is an aftermarket firmware for a number of cell phones based on the open-source Android operating system. It offers features not found in the official Android based firmwares of vendors of these cell phones.' Meaning no Samsung Touchwiz framework (whatever that runs on SGS stock ROM and needs Touchwiz will not run in CM), zero lag and speedy operation. I am not sure what you mean by what's good in CM7 - for me the sheer speed is the biggest pleasure factor. Not having Touchwiz at all is another plus factor. Getting (almost) nightly updates with new fixes, sometimes problems too gives the shiokness that no Samsung-based custom ROM can give.

CM7 also has some additional cool features - read up at http://www.cyanogenmod.com/. Very hard to really explain in detail, try it if you dare

If you absolutely need 'extra juice' as you mentioned, then don't use CM7. On the standard 1500mAh battery, I could barely get 10-12 hours of standby+usage time. With my bigger battery now, 18-22 hours is no problem.

A day as in 24 hours? Hmm, can't say for sure, everyone of us has different usage patterns, different apps etc.

Maybe if you change to 2G only or turn your 3G on only when you need it? As for me, I am a lazy fella, my 3G, BT, GPS and WIFI are all always enabled. 

im using cm7 with fugumod. switch off, wifi, BT, ,gps and im using only 2g.
A lil bit of music (earphone) , read manga on mango app, texting and a lil bit call.
My battery showing 40% for 20hrs.