My issue with it is how easy it is to allocate all over the place if you forget to use inplace operations. It's even worse with cupy - rather than applying a series of operations to some data to produce some other data, you end up producing a set of data for each operation. Yes, there are workarounds, but they aren't as ergonomic (cupy.fuse() almost does the right thing, cleanly, but is a step you have to remember to use, and doesn't really work for anything that requires multiple shapes of array).