Does the LS3 use the DOD system on the VF?
The DOD lifters do have a reputation for failing/collapsing? IF the DOD isn't used, put standard lifters in the sucker and the problem is solved.
As you can see, the DOD lifters are bigger/heavier. If they aren't needed than deleting em is good for piece of mind. I believe LS7 lifters are a direct replacement and can be had for a decent price. That is, if it's the way you want to go.
Do some research on the GM DOD system and lifter failures, it's is a fairly common issue (the DOD part failing that is).