I've used it twice on behalf of clients, and it could just be that they were using really primitive templates, or that Fishbowl is really limited. It sounds like they've got some changes in the works but I never saw them. I had to pull monthly email reports and it ended up being a process of pulling 40+ excel files and combining data into one since Fishbowl was breaking the data up into performance by store. I would have much preferred aggregated data for how each email performed by day - not by store! Not useful information, at least for our purposes. And the need for 3 disparate systems was frustrating too: LSM, Offer Manager and the regular Campaigns/Email. For reporting too, I had to hop across all three to get basic level data.
And a major - (at least when I used it last year) is that there's no automated A/B testing. You have to split up groups yourself and check the results the next day and deploy.
Segmenting audiences is easy once you can figure it out - lots of logic (parentheses, brackets, if, then, only, etc.) and after a major SNAFU of an email going out to people more than once, I decided to call support for every segmented send from then on to have them hold my hand and walk me through that my logic was sound!
Think about everything you want to execute. If you have really complex automations and journeys, I'd suggest looking elsewhere - unless they've upgraded their tool at this point to allow for more sophisticated emails.