Few months ago I've done comparison and testing of spinners for project that I was going to use them for, I've tested 3 or 4 spinners. WordAI does stand out from the crowd with their "Turing Tech" mode.
In my opinion, for auto spin (plug'n'play) was
by far the best one in terms of quality of spin. What I did not like back then, was limit that they have set for usage, if you read closely it says:
If you plan on processing a lot of volume (over 2.5 million words/mo with the Standard technology or 250,000 words/mo with the Turing Technology) contact us to discuss bulk API pricing! Our default pricing is $1 per 100,000 words for the Standard Technology and $3 per 10,000 words for the Turing Technology.
So, with Turing you can do a spin of 250k words per month, and let's say that average article length is somewhat about 600-700w that is actually ~400 articles. At the time, that looked very low to me. In addition to that it was very VERY slow for Turing spinning, but that is not crucial as the limit was.
But, now with WordAI 4 they say:
This new brain is lightning fast! To be exact, WordAi Version 4 is 149.8 times faster than WordAi Version 3, meaning your articles get spun almost instantaneously!
We have increased the Turing Spinner usage limit by 1,200% to 3 million words - meaning you don't have to worry about pesky overage fees or restrictive spinning limits!
Speed wise, it's good. I like that improvement, but it's not crucial, especially for API use, as I can just run it as long as it takes.
What I like the most is now that when you can do 3 million words a month, that actually mean that you can do ~4500 articles a month, and that sounds a lot better to me.
I hope this helps.
Cheers