just use dynagen(back end to GNS3). I dont recommend GNS3 at all.
»hardforum.com/showthread.php?t=1 ··· =1414407
check out my sticky. Its pretty conclusive. For the switch portion, you can do 99% of it with most 2900 switches, obviously read into the 6500 as they mention stuff relating to SSO on that exam.