FestusMcShamus,
The CCNA exam is based on the Cisco 2950 switch, a Cisco CAT 1900 with the enterprise edition of the IOS (so that you have a conmmand line interface and VLANs) will help a lot.
But I would make sure I check the slight differences in the commands between the 2.
I just recertified in July on the new CCNA exam and most of the switching questions were very general and not specific to a 1900 or 2950.
All my practice has been with "real" 1900s but I also did a few configs with a 2950 on a sim so that I understood the difference - just in case.
I have read in forums that there is a "switching sim" on the CCNA but I have NEVER talked to a student of mine who got it.
E.A. Broda
CCNA, CCDA, CCAI, Network +