Depends on your use case

If running models then Apple is fine, if training or tuning or large number of users then Nvidia is king

Two RTX 6000 have more FLOPS and more memory bandwidth than a M5 Ultra (but they also cost more).

There’s roughly 50% more memory bandwidth on an RTX 6000 pro versus the M5 Ultra. I imagine it really comes down to what you’re doing, I know my 5090 runs laps around the M5 Pro I have when it comes to local LLM performance (until it runs out of memory).

If it wasn’t for the fact the 6000 Pro is selling for like 100% ($9,000) over MSRP it would probably look a lot more reasonable.

If your goal is pure GPU compute, you should have got a 5090. It can bench comparable to the RTX 6000 Pro cards and is near guaranteed to outperform M5 Ultra.