I would still use them. I have had this happen before and have never had a head gasket failure.
I once had a GM 350. Upon torquing the very last head bolt, the threads stripped out. I knew that it would need a Helicoil or something like it, so I pulled both heads so the engine would be light enough for me and my brother to hand load it into my truck! I reused the gaskets and had no problems.
Other times I had the heads on and then had a moment of panic..."Did i put the pistons in with the valve reliefs pointing the right direction?"
Once again, no troubles.