This add-on sure found many that other add-on I've tried wouldn't. (I tried Ginger and Grammarly) and it provides suggestions that are very helpful for a person that speaks English as second language. I use this software for my academic writings and I found it handy.
It is, however, slow when it runs the check, and this would be especially significant if your PC is older.They also have a 14-day free trial for premium (I think the free version doesn't really do anything although it would run the check and let you know the # of issues... so, well... the free version is pretty useless). I'm currently using the trial now, and am considering to pay for the service.
