The L40S 48GB has about 42% more memory bandwidth (864 vs 608 GB/s). Batch-1 decode tracks bandwidth closely, so a model that fits both cards should decode roughly 42% faster on the L40S 48GB. The L40S 48GB fits more of the catalog at Q4/8K — 41 vs 39 of 69 models (48 vs 32 GB VRAM). Largest model that fits the L40S 48GB but not the Arc Pro B70 32GB: Qwen3-Next-80B-A3B-Instruct (81.3B). MSRP is $999 for the Arc Pro B70 32GB vs $8,000 for the L40S 48GB. MSRP is a launch list price, not live retail — Amazon prices move; click through for the current price. In the Q4/8K head-to-head below (53 shared models), the L40S 48GB posts the higher tok/s in 52 rows vs 1. Methodology.