I would re torque them regardless.
If you don't, I am sure karma will catch up on you for stealing.

Everything will probably seem fine, but one day, after running fine you will have a catostrophic failure....
...this will be due to the fact that you stole parts....from a fellow mini person.  You should be ashamed of yourself....

Yep...done most of that Al

i've spent some time on this, here is what I found:

The studs need to be assembled/dis-assembled 3x if they are brand new using the suggested lube and to the torque they will be used. This process is required to seat the threads between the nut and stud. The first time the assembly is torqued, the friction will be high, which will result in less clamp load for the same torque, as compared to the fouth time where this flattens out. 

The gasket needs a similar process. Brand new, the head gasket will have lots of spring, it needs to find it's set before final assembly. The gasket too should have three(3) assembly re-torques on it before it is final used. This ultimately effects bore distortion more than anything, but it is important for head assembly too.

 If you want to be anal: flat sand the washer and nuts prior to usage to eliminate any burrs that will effect friction. Keep the same washer, nut, stud together. Go to a torque-angle assembly procedure.

The studs/nuts can be considered junk if: the therads are bad - best to check with a thread gage. if the stud has stretched - measure the length of the studs and compare them.

Multi Layer Steel gaskets need no re-torque after running it in, as long as these, or the fastener/gasket suppliers instructions are used. Composite gaskets will take a 'set' after being heat cycled. Usually their thickness will reduce which causes the fasteners to lose clamp load, which is the reason you need to re-torque.

There is a lot to fastener torque and clamp load, keeping with the basics i've mentioned should get you most of the way.

cheers.

stuff like "torgue to yield" bolts don't need retightening

metal gaskets don't need it but composite does?

aluminum versus iron heads? cheap head bolts (like on Ford V6) that stretch

all sorts of head bolt stuff - anyone have a great article link?

I do them 3 times- on initial build, again when hot, and in 1000 miles (when hot). As CC said it's the gasket that settles in, not the studs.

Adjust rockers each time, of course.

The old mechanic's (like me) rule of thumb is: retorque iron heads when hot, but alloy heads when cold.

I'd say it has more to do with the gasket not the studs.

I recently installed a new head gasket and replaced the old tired head studs with the ARP kit. Now, I know that a re-torque is required with cold rolled studs, but is it really needed when using these new fancy studs? and why? If I have followed the instructions, should I not have already achieved maximum clamping? Does a few heat cycles affect already stretched studs?