I wrote a kind of complex code for MCU which deals with FRAM and few buffers, juggling bytes around in a complex fashion.
I was very not sure in this code, so I spent some time with AI chats asking them to review this code.
4o, o3-mini and claude were more or less useless. They spot basic stuff like this code might be problematic for multi-thread environment, those are obvious things and not even true.
o1 pro did something on another level. It recognized that my code uses SPI to talk to FRAM chip. It decoded commands that I've used. It understood the whole timeline of using CS pin. And it highlighted to me, that I used WREN command in a wrong way, that I must have separated it from WRITE command.
That was truly breathtaking moment for me. It easily saved me days of debugging, that's for sure.
I asked the same question to Claude 3.7 thinking mode and it still wasn't that useful.
It's not the only occasion. Few weeks before o1 pro delivered me the solution to a problem that I considered kind of hard. Basically I had issues accessing IPsec VPN configured on a host, from a docker container. I made a well thought question with all the information one might need and o1 pro crafted for me magic iptables incarnation that just solved my problem. I spent quite a bit of time working on this problem, I was close but not there yet.
I often use both ChatGPT and Claude comparing them side by side. For other models they are comparable and I can't really say what's better. But o1 pro plays above. I'll keep trying both for the upcoming days.