Futureproofing a local LLM setup: 2x3090 vs 4x5060TI vs Mac Studio 64GB vs ???

Hi Folks, so I've convinced the finance dept at work to fund a local LLM set up, based on a mining rig frame and 64GB DDR5 that we already have laying around. The system will be for agentic workflows and coding pretty much exclusively. I've been researching for a few weeks and given the prices of things it looks like the best contenders for the price (roughly £2000) are either: 2x 3090s with appropriate mobo, CPU, risers etc 4x5060TIs, with appropriate mobo, CPU, risers etc Slack it all off and go for a 64GB Mac Studio M1-M3.