If I remember correctly the first time I looked at the marketing materials when I went to their official website and they advertised it to me as an alternative for the free version I was trying, they basically offer(ed) a few features I didn't care about:

1. The very latest model, i.e. this week instead of this year

2. Saving your conversations and using that to tailor the LLM to you

The first was not worth $10/month or whatever it was, and the second was something I actively did not want.

I have a sneaking suspicion that people value the service for its ability to mimic professional human writing, which they are otherwise incapable of, and they don't really care that it's not very accurate.

But it's hard for people to admit, "Yes, I'm an adult who writes at a 3rd grade level," so they pretend it's useful for other reasons.

It's pretty much just unlimited images, and access to version 5 instead of falling back to 4.

Yeah, it's a fun toy that's definitely not worth any money (at present, possibly forever).

In all fairness, recently duck.ai has been adding a "settings" portion to help you prompt the LLM to get much better results, but again, that costs $0 to use. The couple times I've used its "tech support" setting, it's been fairly helpful, but I wouldn't trust it on anything serious (due to how often LLMs hallucinate).