Not sure about internationals. We have one, the next corridor has 2, third corridor has none. Not sure about upstairs and AV.
JM has a better social life. AV has a reputation of being boring and staying in, which is quite true. Although you do find some lovely people in AV that break the rule. Some of my best friends live in AV.
AV has larger rooms, a huge desk and better bathrooms. JM is having new bathrooms being fitted for the start of the year. I still prefer JM though.
JM is either 11 or 13 per corridor, which is 36 per floor. Not sure about AV, but it's probably the same.
Although AV does have it's own laundrette and a lounge for each kitchen, it does have the reputation of being boring, and you personally get a reputation for being some rich toff because you can afford £84 a week. Personally, I love living in JM, although if i chose again I might choose Rootes. Basically because they're more sociable.
I'm sorry if none of this makes sense, I have a stinking hangover.