I don't know c***, but being super a***, I would replace any bolts that have a torque specification, because some bolts get their threads stretched when you torque them. Head bolts are cheap enough, and I'm super a***, so why not?
P.S. anyone that knows me, knows I'm NOT a***, let alone super a***.
First, regarding head warpage, I agree with the Toolman(sorry Toolman). Measure the warpage. Check your block. Can't hurt.
Warning- Soap Box. Not meant to be critical, just vent.
To be clear, I think most would agree every bolt on a motor has a torque specification, even the valve cover and oil pan bolts. But you certainly don't need to replace those every time you loosen or tighten them.
Also, when I plastiguage my crank and rod bearings/journals(another subject), I certainly am not going to put on a new set of bolts between inspections. And, although I don't have my torque table in front of me, I think the torque values are at 105ft.lbs. +/-10. I don't think those torque values are going to hurt those bolts.
For what it is worth, here is an ASE web page:
http://www.freeasestudyguides.com/a1_4.html
However, they do not mention(or I missed it) you need to do a very good visual inspection of the bolts. On my first motor, 150K mile Windsor, a couple of bolts were a little rusty from a tiny head gasket leak. The fact this may be an issue may make a head bolt purchase a wise decision. (To extend this post, but to be clear, the motor was rebuilt at 140k by a "reputable" builder, and they reused the obviously rusty head bolts. Thank you Orange Engine)
And regarding a***, I am just tired of throwing money away because it "seems" like the right thing to do. Money on head bolts, main bolts, rod bolts, intake manifold bolts, water pump bolts, fuel pump bolts...there is real change there. $150-$200? Not to mention the time to find them, order them, store them...lose them, find them. ugh.
And, everyone here has had a bad aftermarket part experience. Does anyone really believe the words "BOLT ON" mean bolt on? And, now we are actually talking about THE BOLTS. (By the way, does anyone besides me wonder why no one makes an engine mount bolt? If these aftermarket guys are so good at making bolts, where are the long engine mount bolts?)
All this being said, do I reuse my head bolts. No. Can I justify it? No...well not the UNrusty bolts. If I had $10M bank I would test NEW bolts versus OEM bolts just for fun. But until then, I buy into the propaganda. But I am looking forward to the day when I can be pointed to something other than propaganda.