I have usually 4 concurrent requests/agents running on a single 5090 (plus 64GB RAM) on a Windows to that (exllamav3, Qwen3.8 27B 4bpw HQ with 6bpw LM head etc., q5,5 256k context kv cache with lvl2 8gb vRAM KV cache and lvl3 SSD one (50GB). Over 200T/s in many cases, still have vram to spare but this has been tuned with my own harness and quality benchmarks compared to 8,8 KV and other variations. Point being, I don't need Spark to do that already, I don't see a reason to have one for such use. I wouldn't mind one, like I wouldn't mind 96GB vRAM for FUN, though - a hobby these days for me but can't justify it with those prices. Still, a single 5090 is already plenty good at home really IMHO. Granted, bought for MSRP as prices these days are ridiculous.