Before making any decision on studs V.S. bolts, I suggest reading the ARP catalogue. The front section deals with repeatability, clamp loads, stiction (static friction) relating to bolts, grading and metalurgy of fasteners, why use washers, and MUCH MORE. I am totally surprised at how many "engine builders" and machineshop owners that have not read and familiarized themselves with this free info! Before ARPs wonderful catalogue, I read a lot of the fastener/ thread systems section of the MACHINERY HANDBOOK, it too contains a ton of great info, but more oriented towards industrial usage than automotive, but a worthwhile read too.
Back to stiction, it is static friction, in this case mostly applies to torquing bolts.
In short, when torquing a bolt, part of the torque that should be used for clamp load is actually used up in friction between the bolt head and cylinder head. Thats the why you should use lube under the bolt head, and preferably a hardened washer also. When torquing bolts without washers, I have a 1" diameter 6" long round aluminum bar that I use as a punch, I put it on the bolt head, and give it a sharp rap with a hammer to "shock" the bolt shank to relieve the frictional twist the bolt shank has in it. Try it sometime, then retorque. You may be surprised at how much torque is lost. This is only one place where studs are better; hardened washers, ARP lube, on studs, tend to not build up twisting stresses as much as bolts do. Me, being anal, I hit studs too, but the torque loss is much less.
Also, if torque plate honing blocks, and you should, use the exact same fasteners as you will be doing the final assembly with. And never replace main bolts with studs without line honing the block. Studs give approximatly 30% more clamp load than bolts, and that distorts the main caps differently, causing an out of round condition.
Why do studs have more clamp load? and torque to higher levels? When machining an engine at the factory, they machine the main threads deeper than necessary so the bolts don't bottom out.
You install the studs about a quarter turn up from the bottom, giving more thread engagement, plus the top thread is a finer thread than the bolts, because of that, the "ramp angle" of the thread is flatter, resulting in more clamp load per foot lb. Torque.
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