No-one has yet pointed out that it has a graveyard, and a very fine crypt.
I feel these are important points to consider.
The only disadvantages I can see are its rents, and the fact that on some souvenir mugs it is referred to as 'St Edmund Hall College', which is just embarrassing.
Have been to the graveyard but not to the crypt... haven't seen any other colleges with proper graveyards- at least, none that I am aware of. There is LMH which might share the same fate of SEH on souvenir mugs
The graveyard only has a few headstones dotted about otherwise its a nice informal grassy area. At least you can walk on the grass, unlike some colleges where you have to a fellow to walk on the grass.
i looked at the virtual tour (www.chem.ox.ac.uk/oxfordtour) and SEH looked really cool with the graveyard, and the front quad is nice looking too. Isn't it the oldest educational establishment in Oxford, too? I thought it looked like a really cool college, actually. Although - and this is stressed enough - the differences between them are minimal, and the differences that would have a major impact on your uni lifestyle you couldn't possibly be aware of anyway just now.