Hello everybody. I'm calling from Belgium.
I've a 64Gb 3G iPad In iOS 4.2.1, JB first with RedSn0w and then with GreenPois0n RC6 over it (so no need to install Cydia again and still have the apple logo when booting.
All is working perfectly fine.
Happy to read from you and to give you some help issued from my experience and little knowledge in the domain... :)