Multi DB or Not?

I’m trying to determine if I should go ahead and set up Multi-DB. I will be using the Supporter plugin but haven’t installed it yet. I can forsee possibly having several hundred websites (maybe not immediately but soon) as I will be marketing free sites (with upgraded features via the Supporter plugin). I noticed that there were some special database tables and sql queries that need to be done when using Multi-DB and the Supporter plugin, so I’m wondering if I should do it now or wait til later. How difficult is adding Multi-DB later on down the road? What are the general steps to migrate the current database tables? Would there be any issues with upgrading later while running the Supporter plugin? Thanks!