Freemium is perfect for entertainment products where value is subjective so users need to be enticed with a try before you buy mentality.
With a B2B product, I think the best solution is a trial period to lock the user into the project, and demonstrate value over the long term before asking for money.
Stormpulse is now B2B, but we started with a multi-year "free trial" for millions of people - i.e. freemium. This was obviously critical for distribution / adoption, but ultimately wasn't profitable.
I checked out the site. Nice! The paid tiers are named "Entry" and "Operational", whereas the free trial tiers are "Entry" and "Enterprise". Shouldn't the names of the free tiers be consistent with those for the paid tiers?
With a B2B product, I think the best solution is a trial period to lock the user into the project, and demonstrate value over the long term before asking for money.