if i were you, do not fully rely on GNS3, its a great router sim dont get me wrong, but switching is crude.
if you want to do more switching type sim's use packet tracer. or even better, hardware
gns3 - no switch work, bgp is buggy as well.
packet tracer - no HSRP, ether channel is a little buggy ( shutdown any interface before adding to your channel group, then bring them up )
so use both to your advantage, you will not be able to intermingle them, but i think you can use GNS3 and a 2900 switch and emulate that way. something to keep in mind.