PyNN, Nest and SpiNNaker

We've been working with PyNN, Nest and SpiNNaker for about 10 years now.
There are some minor differences between Nest and SpiNNaker when accessing them via PyNN, but these are adressed relatively easily with global variables and conditions around certain areas.
There are also difficulties with versioning as new versions are not necessilarly compatible.
Occasionally, SpiNNaker is really useful for large versions of the systems.
However, we usually work with Nest in the first instance, as you don't need a board (and the internet version of SpiNNaker can be a hassle.)
So, we always write in PyNN.