Anyone actually tried GPT-5.5 yet? Is it worth the upgrade?

I’m seeing a lot of hype about the new GPT-5.5 'Spud' update, but I’m still on the free version (using 5.5 Instant).

For those of you who have the Plus or Pro plan is the 'Thinking' mode actually a big jump from the older versions? I’ve heard it’s way better at coding and logic, but I don't want to drop the money if it's just a small change.

Should I go for it or just stick with Claude for now? Curious to hear from anyone who’s actually put it to work this week