Just a follow up post to say that the Seagate GoFlex USB 3 has been behaving pretty well except in a particular situation when one plugs in the disk when the MBA is at the login screen and immediately logs on without waiting for the disk indicator light to come on.
In this situation, sometimes the disk is recognized and others it is not.
This state of affairs results when one closes the lid and sends the MBA to sleep without logging off.
When you do that, the MBA will become finicky and occasionally will not recognize the disk. This is usually resolved when you unplug and plug it in again.
To remedy this situation, one needs to perform the pre SMC reset steps described by apple : first make the computer sleep, then wake it up, then restart it, wait for it to restart and then shut it down.
Intel-based Macs: Resetting the System Management Controller (SMC)
Once these 3 steps are done, the disk will be recognized even when you login before the disk indicator lights come on.
To ensure that the disk is always recognized, one has to logout every time you put the computer to sleep. If you logout every time you put the MBA to sleep, everything is ok.
Looks like the sleep/wake process is buggy for Lion and USB 3.0
Looks like more work needs to be done by both Apple and/or Seagate to make the process smooth.
I hope someone from Apple or Seagate is listening - pls try to make it better for everyone.