Simon, what is your local GPU setup? (No doubt you've covered this, but I'm not sure where to dig up).
Are there non-mac options with similar capabilities?
The unique benefit of an Apple Silicon Mac at the moment is that the 64GB of RAM is available to both the GPU and the CPU at once. With other hardware you usually need dedicated separate VRAM for the GPU.
0: https://www.gmktec.com/products/prepaid-deposit-amd-ryzen™-a...
On my M1 Max macbook pro, the GGUF version bartowski/google_gemma-3-27b-it-qat-GGUF is 15.6gb and runs at 17tok/sec, whereas mlx-community/gemma-3-27b-it-qat-4bit is 16.8gb and runs at 15tok/sec. Note that both of these are the new QAT 4bit quants.