Question: Who should I ask to proofread my MSc dissertation? Is proofreading required?

Answer: 
I'm now reading the Msc dissertation of a friend but being brutally honest in my comments which she happens to like. It does help that I once was an archaeology student myself. But I think that the more people who read your dissertation before you hand it in, the better. The process of writing up a dissertation isn't just about writing it all up. It's also about being able to form up your own opinon, being critical, being able to work together with other folks and work on your own at the same time.
**Easy and Rewarding Solution!**: First, find a trust worthy class mate who DOES NOT do the simillar dissertation. Second, offer to read his/her dissetation, in exchange he/she read yours. Third, discuss each other dessertation after the reading is done. Fourth, fix your issues. Fifth: repeat if you have more time until you are confident with your dessertation.