Claude Opus 4.6 vs. GPT 5.4

Claude Opus 4.6 vs. GPT 5.4: My Take as a C#/.NET Dev on AI Coding Companions Alright team, let's talk AI. As a senior engineer who's spent more years than I care to admit wrangling C# and .NET, I've seen my fair share of "game-changing" tech. Most of it is just hype. But these new-gen LLMs? They're different. We're talking about legitimate productivity boosters, especially when you're staring down a tricky bug or architecting a new microservice. Lately, I've been putting the big two — Claude Opus 4.6 and GPT 5.4 — through their paces specifically for coding tasks. The question isn't if they're useful, but which one to bring to the fight, or if we should be thinking "both." Let's dive into my real-world experiences. The Setup: My C#/.NET AI Playground Before we get into the nitty-gritty, a quick word on my testing environment. I wasn't just asking them to write "Hello World." I was throwing real-world problems at them: building complex LINQ queries, designing a robust API controller, r