Main Studs??

The align honing I thick is a personal preference. The only differences between a bolt and stud are the forces applied to the fastener which could or could not cause failure depending on application.
A bolt has two different forces in which it is used, one is a rotational force since you a screwing it into a thread, and the other is a clamping force or holding force to what ever it is securing
A stud only has one force applied to it when tightened and that is clamping or holding force.
So if you clamping with a stud it should not distort unless you do not torque it properly.
Also here is a little read that my be helpful also.
Engine studs: Understanding the advantages of using studs vs. bolts, and tips on achieving proper clamping loads - Automotive Service Professional
http://www.autoserviceprofessional....dvantages-of-using-studs-vs-bolts-and-tips-on

May I add also GOOGLE, YAHOO, and other search engines can be very informative if the right key words are applied