I agree that the show had a fairly strict premise but that is what made the show different than just about everything else when it came out. I would also argue that the premise did get challenged occasionally during the 7 seasons. For example, in the episode The Innocent, a normal citizen is manipulated into helping with the mission.
I have all 7 seasons on DVD already and wasn't planning on getting this Blu-Ray set until I read the review posted above. I am a little disappointed there are not any extras included but will probably still pick it up. Thanks for being a bad influence Mr. Mike. =)