It's nowadays not funny anymore to do business or events in Second Life. The rule of the thumb is: the more people are online the same time, the more instable and slower the grid becomes. We had an event yesterday in the garden, the sim is able to hold 40-42 people at the same time. The owner even requested a reset of the sim one hour before the whole thing started.
And what happened: About 30 minutes after the event started, the sim was full, the whole sim crashed. We were lucky it crashed only one time, though, other sims have been reported to crash several times on Saturday while being full, e.g. for a wedding.
So, what are the consequences you should make? Well, it's obvious, though SL is an excellent platform, that it has got major scaling problems at the moment. So, if you really want to do events in it or make serious business or teaching, better find dates where not so much people are online, to get a better experience of the grid. It's probable that when there are many people online that the grid is going to behave strange and has hiccups, again, and this is getting worse day by day at the moment.