Siemens S7/400 with Beckoff

Can same one please tell me if they have ev ery use a beckoff remote I/O with a S7 400 PLC. We are busy to built a new plant and this is what the supplier of the plant gave us.

If you have use it, are there any problems that I have to look out befor we sign it off.

We have beckhoffs profibus io with no problems.

The beckhoff analogue I/O I've used does not scale the same as Siemens - so FC105/6 is of no use.