nofam: Yes, as wazz/lokhor have said, flashing kernels doesn't touch the bootloader (AFAIK), so unless something goes horribly wrong, you should always be able to reflash from Odin.

The proviso here is that you can get into Download Mode to use Odin, so you must ALWAYS make sure you can do this before thinking about using Odin.

The other essential thing is to use root explorer to grab a copy of /efs, and stow it somewhere on your PC (or external SD card).

Shrapnel:

nofam: Yes, as wazz/lokhor have said, flashing kernels doesn't touch the bootloader (AFAIK), so unless something goes horribly wrong, you should always be able to reflash from Odin.

The proviso here is that you can get into Download Mode to use Odin, so you must ALWAYS make sure you can do this before thinking about using Odin.

The other essential thing is to use root explorer to grab a copy of /efs, and stow it somewhere on your PC (or external SD card).

Thanks for everyone's replies, so this is where things are getting confusing for me. So download mode? and efs?. 2.1 ain't running to bad at all for me, I put it up against my brothers Iphone 4 and it was the same speed(or faster) loading things like paper toss, contacts, music player and the phone app so I can't complain on speed to much(50ish apps installed).

EDIT: Also the warranty is kinda important to me and this will obviously invalidate it, Right? 

1. Put your phone into download mode using the three-button-combo:
   Press and hold VolumeDown+Home+Power buttons till the phone enters download mode


2. 
   

Shrapnel: It all seems a little complicated, I may consider it. We'll see, man everyone replies fast here

bsd1:

Shrapnel:

nofam: Yes, as wazz/lokhor have said, flashing kernels doesn't touch the bootloader (AFAIK), so unless something goes horribly wrong, you should always be able to reflash from Odin.

The proviso here is that you can get into Download Mode to use Odin, so you must ALWAYS make sure you can do this before thinking about using Odin.

The other essential thing is to use root explorer to grab a copy of /efs, and stow it somewhere on your PC (or external SD card).

Thanks for everyone's replies, so this is where things are getting confusing for me. So download mode? and efs?. 2.1 ain't running to bad at all for me, I put it up against my brothers Iphone 4 and it was the same speed(or faster) loading things like paper toss, contacts, music player and the phone app so I can't complain on speed to much(50ish apps installed).

EDIT: Also the warranty is kinda important to me and this will obviously invalidate it, Right? 

Download mode is a way of starting the phone so it is ready for manual updates and this is done using a boot while holding down three buttons:

1. Put your phone into download mode using the three-button-combo:
   Press and hold VolumeDown+Home+Power buttons till the phone enters download mode


2. [removed pic to save space]

2. The EFS is a folder on your Samsung that contains the phones IMEI number (unique identifier) and Product code.

Wipeout: I've giving up on Samsung a long time ago, after they blatantly lied to me. Root your phone, back up your current firmware for warranty and don't look back with a new custom rom, imo. :>

Anyway, flashed Doc's new 7.5 base with a custom theme (cozmic) and the same hardcore kerner I've used in the previous Doc's base release from the kitchen ('i"). Incredibly quick. Now I will just wait for some other kernel to come out, but it has to be something really outstanding for me to change. 

Here is my log of the new Rom, in case anyone is interested:


This is a log file genereted using http://romkitchen.org

This ROM is using the XXJPY_Wipe.zip ROM, coupled with a hardcore_12i kernel and a jpy modem.
The theme is the cozmic theme.
WPA is standard.
The default keyboard is the samsung samsung_stock_jpy keyboard.

The exact structure of what's included:


swype_jpy keyboard
|
|-> system/app/Swype.apk
|-> system/lib/libSwypeCore.so

Root
|
|-> data/app/Quickboot.apk
|-> data/app/SGS_Tools.apk
|-> data/app/Spare_Parts.apk
|-> data/app/FasterFix.apk
|-> data/app/LCD_Density_Changer.apk
|-> system/app/AdwLauncher.apk
|-> system/app/com.ebproductions.android.launcher.apk
|-> system/app/ScreenCaptureService.apk
|-> system/app/FMRadio.apk
|-> system/app/Music_aosp.apk
|-> system/app/ChocoEUKor.apk
|-> system/app/CoolEUKor.apk
|-> system/app/RoseEUKor.apk
|-> system/app/Mms.apk



Oh and the gingerbread launcher is crap. Apart from gingerbread style scrolling in the app draw, and two different colored icons on home screen, it has nothing to offer. In fact those two icons on the home screen can not be changed! So you're stuck with phone and internet icons. hahaha... :| 

Wipeout: The theme did come with an extended power menu. None of those apps in the log are actually my apps, it's those that I chose from the kitchen. I do have a pile of apps which have been backed up by TB tho. Have reinstated all of them without any issues.

I just connect to the laptop via mass storage device. I don't see myself ever using that piece of sh*t software (Kies). hahahaha... Mind you, I had to make sure my phone's drivers installed correctly on my laptop before I used Heimdall. Then I had to install Heimdall drivers on the top of that. So my phone is now gets picked up within two seconds of plugging it into the laptop and brings up both drives (sd/ex_sd). I just drab and dump. :>

nofam: Just in the interests of thoroughness, do you guys (as a rule) pull your SIM and external SD before flashing ROMs via CWM?

Or do you only do this in a 'rolling up the sleeves and getting rather firm with the phone" situation?