I was experiencing softupdate inconsistencies and actual data-loss in 4-stable on my main workstation which has a large 30gig EIDE drive on it. Turning off softupdates and disabling dma in -stable made most of the corruption go away, but it was still there.
I decided to upgrade the workstation to freebsd-current and see if ATANG would fix my problem. So far it has fixed the disk issue, but it broke my mouse. ums(4) is losing interrupts and the mouse is unusable. I have to attribute this to my chipset and the new interrupt code. I'm going to be playing around with different settings to try to get my usb trackball back, currently I'm recompiling with NO_MIXED_MODE to see if this might fix my issue. *cross fingers*
I notice that ULE still needs some work however, I experienced several instances while buildworld/buildkernel is humming in the background where apps never get slices or not enough slices to continue correctly (most visible with knode).
So far -current is fairly stable if I ignore the ums issue and use the trackball in ps/2 mode with the adapter.