Problems or No Problems Major Modifiers Speak Up
FWIW, Im currently running an opti that was on my old motor for about a year, its been on the new motor since install without a hitch.
The only problems I had were directly related to custom, one-off stuff I did to this motor, particularly the fuel rails and the modified timing cover. The fuel rails were modded heavily, and leaked at first. The timing cover was modified to accept a BBC crank seal, as my balancer hub has the BBC o.d. When doing break-in, I had that seal walk out of the cover and my car got an oil bath on her bottom side.
Other than that the car ran great, untill I took it off the road for more mods. It'll be runnin again by the end of the month, towards the beginning of next month.
As was said before, everything breaks, but its no more common on LT1s than anything else. 
