Precis of my new article, forthcoming in Nature :
Recent research in the field of Advanced Cheesesteakology definitively indicates Ma Magoo's and I Chef are approximately 2 standard deviations better than your average Boston area "steak and cheese" (normal dist.), with I Chef having the edge.
Requests for a "cheesesteak with fried onions" at Ma Magoo's were translated at the counter into "steak and cheese with cooked onions" instructions for the cooks. Although some commentators have suggested the mere fact of this translation, in the absence of data loss affecting integrity of the resultant cheesesteak, is a red herring, we believe those commentators are dumb (and we will go out of our way in this article to passive aggressively malign them). No similar translation was required at I Chef.
Both establishments use quality rolls. They are crusty but pliant and not annoyingly brittle. Both were reminiscent of Amoroso's rolls from the author's misspent childhood.
Both establishments used the correct cut of meat and handled the requisite cheesesteak cooking equipment with something approaching legitimate aplomb.
I Chef distinguished itself in its handling of the applied American cheese. Too often in Boston, American cheese is added atop the cooked and integrated mass of beef and onion at an acceptable time but the whole is then almost immediately removed from the heat source. While economically efficient, this results in a mostly solid cheese situation (read: debacle), usually resident as a discrete layer separating the meaty mass from the roll and being otherwise generally depressing.
Analysis of the Magoo's sample showed the cheese in an intermediate phase, the result of only slightly premature withdrawal. Since the norm in the area is radical prematurity, this finding is a positive one.
The I Chef sample was masterful. The cheese had been allowed to mature, melt, and comingle with the shaved lovelies, resulting in a comprehensive cheesiness throughout the sandwich (N.B. Research indicates that "comingling with the shaved lovelies" is devoutly to be wished in multiple contexts; a follow up study will explore this in more detail). Additionally, the I Chef sample was almost flamboyantly huge.
Both places are recommended, although the author cautions that cheesesteak quality is heavily dependent on the individial cook and results are likely to vary between samples. Followup research is being conducted to determine if there is a stastically significant relationship between establishments which do not require dynamic translation of "cheesesteak with fried onions" into local dialect and overall cheesesteak quality.