What Limitations Could I Reach in Terms of Flows Created in One Design?

The more I use flows, the more situations I find where I want to use them.

Are there any practical limitations I may find in terms of the number and size of them that I have defined in my design?

I know these things are hard to quantify, but I’d be interested to hear if there are any measures I can take of how much resource of some kind they are using and how close I may be to that limit.

Thanks!

Antony.