Best sub-version of Online 7.x for upgrade (AIX)

Hello - I'm looking for opinions, experiences, etc. related to this one: Do any of you have a preference or recommendation as to whether there's a reason to prefer a particular sub-version (say, 7.1x vs. 7.2x vs. 7.3x), in upgrading an rs6000 machine, AIX 4.1.5, currently running Online 5.02. This machine is used almost exclusively as an Informix server in a production environment, and its database contents are considered critical. Most of the users (typically not more than ~65; projected growth perhaps to ~ 100) during business hours use the database interactively, running sql queries, updates, etc. via a text-based menu interface. Larger batch jobs are usually run during off-peak hours. The machine has 512MB of physical memory, and ~15GB of disk space. I've heard that there are specific bugs, problems, etc. related to specific releases on specific platform, and since whatever choice is made for this upgrade, we'll probably live with it for quite a while, so I'd appreciate any input. I'd also like to be able to have both 5 and 7 installed on the same machine for a while, during the transition - the two instances would be using separate dbspaces, and would NOT be running at the same time. Is there anything in the choice of version that would affect the practicality of doing that, or which would affect the possible future use of this machine in a shared environment with another (non-AIX) Online server? Thanks for any input... Don Miller Network Operations JFK University