Spoiler: overpriced for its early stage.
I currently use the majority of Ai content writers (all the big names) but sometimes new gems are discovered (like Contentforge or Texta.ai), other times after testing unfortunately You don't fall in love with the product.
This is my experience with Gocopy:

PRO:
"Instruct" is interesting, maybe it's my fault (and Support info are very very limited) but I could not get more than short output and same text written 2 times. Asked for support, Brent replied late.

CONS:
1- Too simple (less than basic) UI.
2- Many words are hard banned (could not get text about tv series "Sex and the city" - forbidden word! - where other AI engines work flawlessly).
3- Output text is good, but it is sometimes mixed (2 languages at the same time)

For reason #2 and #3 I had to refund.
I think that Gocopy could be really much more than this and Brent is a good young developer, but at present time it's overpriced for its too limited output.