The ISS and SuitSat will be using the same type of antenna. The ISS puts out 10 watts and the SuitSat will be at .5 watts. So it will be quite a bit weaker. If you have two rigs, tune the other one to 437.80Mhz. The ISS will be retransmitting the SuitSat on that freq if it can pick it up.
At first the SuitSat will appear slightly before the ISS, so set your tracker for ISS and begin listening a few minutes early.
Sorry if you knew all of this already.
I have not talked to an astronaught/cosmonaut, but I have heard them talk to other hams and give school interviews. I am a 'ham' with a packet station and have signed onto the ISS bulletin board, with limited success. I usually use the ISS station as a digi-peater and have worked a dozen or so states, Canada, Mexico and Cuba.
Good luck! Red