Freemium

My SaaS product is freemium, though it's B2C and available on the App Store and Google Play store, so I don't know how relevant my experience may be to you if your company sells a web-based B2B SaaS product, for example.

Anyways, here's a few thoughts...

The Good

• Freemium does not equal distribution, but if you have some distribution freemium will enable lots of people using your product. This opens the door to ab testing and learning with statistical significance.
• You will get lots of feedback and can conduct interviews and such fairly easily (there will always be someone willing to talk to you).
• More people using your app (probably) means more people sharing your app with friends, co-workers, family, etc.

The Bad

• The vast majority of users will not pay you, and you will have to support them (via customer support, features, database considerations, hosting, etc).
• Customer support deserves its own point here - even with lots of energy spent developing self-service resources, there will always be support emails to respond to.

Freemium has worked very well for us, though again due to the nature of our product and target market, we're pretty well suited to this business model.