I am not sure what point you are at in the unrooting process but i would 'think' that you would just need to turn the S-off to s-on and then start rooting again... 
there is always the potential to brick your phone no matter what radio you are using... YES, some radio's, according to other forums, are more stable than others... BUT, even the most experienced developer or user can experience a bricked phone for no reason, especaially using the new gingerbread radio with a froyo based ROM (according to other forums)
us 5% of android users that like to play around with our phones are doing it at our 
own risk.. I have been using the MR2 radio with dasBAMF2.0-6 with no issues at all, but others are experiencing reboots and issues 
 
one way that I keep up with all of this stuff is following certain people on twitter, hit me up via PM if you use twitter, and I can give you a bunch of developers to follow. it will keep you ahead of all this and up to date with alot of great android stuff