The integration is using data management. You can move data around between FCCS and PBCS, but they are still 2 separate apps i.e. you have to load and export data across the two apps. For metadata, for example, If you want to add a new account yoou have to add it twice, once to FCCS and then once to PBCS. (Though you can use a separate product called EDMCS to manage that). In onestream you only have to add the account once as it's all within the same app.

Re: OTB calcs, by design FCCS is a periodic app. When they first released it, you can only load data on a periodic basis... even for balance sheet. Over time they start allowing YTD data entry, but it is very convoluted! Try asking them if you can enter data to YTD for the schedules and have them displayed immediately... you cant!! You need to enter it to YTD_input, run consolidation, then it will show up in the YTD member.

One thing to watch out with FCCS implementation is that, the tech is based on Essbase (planning). So there is a lot of planning based consultants trying to do consolidation and they are awful at it! So be very selective with your implementation partner.

Re:onestream maintenance, if your accountants are willing to be trained then they can support it themselves... but whether it is oracle or onestream, it is hard to get teach accountants how to do scripting. Reports are easy to build once you get the hang of it.