upgrading latest firmware 4.3.4 preserving the baseband and unlock in 3gs

[medxx]

i have an iphone 3gs am running on 4.1 version with he baseband 6.15.00 and unlocked by ultrasnow and jailbroken by redsnow.
i wanted to upgrade my firmware to latest 4.3.4
is it possible to do that for me after my baseband has been upgraded to 6.15.00?
will my phone still be ablt to get unlocked by ultrasnow ?
if yes then where can i find a reliable tutorial that i can blindly follow as a noobie! to do all the stuffs !

your opinion will be highly appreciated!

btw! is there a chance ios 5 is coming pretty soon! is it wise enoughh to wait for ios 5 or upgrade on 4.3.4!
ive heard about pdf issues regarding latest firmware jailbreak ! is it safe for me to upgrade!!!

thanks in advance
medxx

[Mes]

My advise? You've waited this long, wait a little longer for 5.0. The latest 4.3.4 has not been fully jailbroke.

[Tazz229]

It's possible to upgrade yes but there's a real chance of turning your phone into a brick!!

My advice is DO NOT update passed 4.1 if your using iPad BB. Many people are reporting no service or signal after doing so.