Kies isn't worth rooting for IMHO, I use google for my personal contacts and am connected to exchange for my district business contacts.
What is worth rooting for is the ability to do a nandroid backup (clock work mod rom manager) and Titanium backup for your apps and data, as well as the voodo lag fix.
ATK is a hinderance when you go to 2.2 the stock process manager does a better job I have found out. I am running designgears cognition 2.2 beta 9.1.1 right now going to flash again soon.
The wife is running dg's eclair cognitiion 2.1.7 going to flash her up to the same level as mine once I am satisfied with his froyo build.
Neither of us have had random shutdown problems, personally I would warranty the phone Stan, I have a ton of apps and crap on my phone and no issues.
I don't have a clue what any of that said other than the last paragraph.
I deleted several apps, and it has, thus far NOT shut itself down, but only time will tell.
Any idea what the warrantee service is like? I won't be happy if I have to send the bloody thing back and wait two weeks (while paying for all the services mind you).