You can do most day-to-day tasks in multi-user mode without noticing much difference
Tasks that take a long time to complete, such as running large reports, can
affect performance for other users. A few tasks, like finding transactions,
temporarily prevent other users from working on the company file. Consider doing
these tasks when other users are not working in the company file. For the best
performance when completing these tasks, use the computer where you store your
company file. If that computer is not available to you, use the fastest computer
connected to the network.
You can also improve the performance of day-to-day tasks by modifying your QuickBooks preferences.
In the Reminders preferences, select "Don't Remind Me"
for tasks for which you don't need a reminder.
In the Reports & Graphs preferences, select "Prompt
me to refresh" or "Don't refresh." Refreshing reports automatically
can slow performance.
QuickBooks Enterprise Solutions offers
About improving performance in multi-user mode