1) yes. 2) no. 3) no. ...there is a minimum guaranteed performance level for each instance type. for small instances (1 core), each user gets a minimum of 1/N of the system resources. If you fire up an extra-large instance, you essentially get the whole box to yourself, including I/O.

see: http://docs.amazonwebservices.com/AWSEC2/2008-02-01/Develope...