I have tried to use both Contact GroupU and Acontacts to email a group of 30 people. In both cases, there was a connection error and the email did not go through (I found this out 3 weeks after sending an email, I thought, through Contact GroupU when looking in my outbox for a change!) I believe emails to a group of 9 when out fine.
Both apps created groups from my gmail contact list.
Anybody have any thoughts about this? I can't find anything in settings or in the email app set up. I am using a Droid, 2.2 and using Verizon as my email client.