I worked at the Royal Alexandra Hospital, Paisley until 9 months ago and was the Deputy Systems Administrator on our SEMS system.
From an administration point of view (we were running it on SCO Unix until April last year when we switched to Red Hat) its not the most friendly of environments if you've not much experience it these types of OS's, although moving to Red Hat was a step forward. The writing of reports using RGEN seems like a bit of a black art at first, but take time to get to know it and its quite powerfull. On the plus side, Red Hat is much more stable and secure than any of Bill Gate's offering to date, and once you get your head round Linux it's relatively easy to follow.
We didnt use any of tha additional modules for SEMS and certainely didn't use it to anything like its full capacity, but for the job we used it for it proved functional and stable.
Around the time I left they were in the market to change / update the system, either to the windows version or a competitors product. Each of the other products had pro's and con's since our system was already tailored around SEMS. As far as I konw they are no further down the line as the Systems Administrator left the month after me and niether of us have been replaced yet.
From a users point of view, ther terminal window look wasnt liked to much and the layout wasnt everyones cup of tea, but after several years of getting used to it, it became the norm and other systems we tested 'seemed' awkward to use.
I'm not sure how IBS stand as far as demoing the product but I wouldn't rule it out without speaking to existing users and taking a look at the product in use, possibly even by visiting another site that implements it.
As a final note, where I work now uses its own in house database written in Access by the Physicist here, which I have found a lot more restrictive than SEMS was.