Thank you all for your advice. It has been helpful to read you. I think we will be looking into open source data integration as it seems to be the most flexible option in regards to our business.
A question: what are the assistance and training capabilities open source software gives to their users? We have downloaded a few solutions - downloads include Talend we are enjoying - we are testing and feel that one day, we might need a better insight of the software.
Open source is an interesting solution. And support and training can be given when you use an open source solution. When using an open source software, you can get support and training. You can also get some free community support from community forums.