Gemma 4 31B vs Qwen3.5 397B

Treat this as a split decision. Gemma 4 31B makes more sense if you want the cheaper token bill or you need the larger 256K context window; Qwen3.5 397B is the better fit if coding is the priority or you would rather avoid the extra latency and token burn of a reasoning model.

Gemma 4 31B and Qwen3.5 397B finish on the same provisional overall score, so this is less about a single winner and more about where the edge shows up. The provisional headline says tie; the benchmark table is where the real choice happens.

Qwen3.5 397B is also the more expensive model on tokens at $0.60 input / $3.60 output per 1M tokens, versus $0.00 input / $0.00 output per 1M tokens for Gemma 4 31B. That is roughly Infinityx on output cost alone. Gemma 4 31B is the reasoning model in the pair, while Qwen3.5 397B is not. That usually helps on harder chain-of-thought-heavy tests, but it can also mean more latency and more token spend in real use. Gemma 4 31B gives you the larger context window at 256K, compared with 128K for Qwen3.5 397B.