I think multiple sims is more preferred because it gives the uni alot of flexibility. i.e. it doesn't matter that we have 10 different sims, because if 3~4 will always be active at different times, there is always something going on. Having your own sim gives you some personal flexibility as well, as you arent necessarily obligated to "show up" unless you want to.
Honestly, the management isnt a huge issue. Just make a Microsoft Spreadsheet or Excel file and you're good to go.