ok i measures this yesterday as there has been much discussion on the issue
keep in mind this was a rwd block. I am unsure is the are different to the fwd, or even if there is a difference between de or ve. However i assume they are all the same.
the holes in the block all vary, from around 82mm up to 91 or something, anyway they are all different. However they all have the same amount of threads, so each hole has 45mm of thread. On the oem bolts most the threads are not actually used.
Now the arp's i have are the new tensile ones. The threaded section Measures in at 30mm. So there is 15mm of unused block thread.
So the extent of the difference from the pictures posted means jack, as the other studs can have double the threads but only 45mm will be used which is 15mm more than the arp's that i measured. If anyone has different measurements for the arp's i would love to see them.
So from this i have concluded that the arp's are better than standard, but not quite as good as the greedy or tomei studs. But for the cash of those i would rather 1/2 inches.