We have not had scalability issues. I tried to anticipate this. However, IBM has you covered in this respect as it is dedicated.

Scalability has been a problem area. We have traffic on the order of gigabytes and it impacts our queries and responses a lot. Considering the volume that we have, it manifests itself into a multitude of issues.

We have not had to deal with this yet. My client has bought the smallest option, i.e., 1TB. We understand that this is scalable but my first client is unlikely to need anything more than this.

We did not encounter any scalability issues during the project.

We did encounter issues with scalability. Even with a MPP instance, scalability is not transparent.

To add a node, we need to raise a request and there is downtime associated with it.

No scalability issues. 

The way that it scales will help a lot of customers that are stuck with Netezza boxes that can't grow any larger.